93 DBMS_SCHEDULER

The DBMS_SCHEDULER package provides a collection of scheduling functions and procedures that are callable from any PL/SQL program.

See Also:

Oracle Database Administrator's Guide for more information regarding how to use DBMS_SCHEDULER

This chapter contains the following topics:

Using DBMS_SCHEDULER
- Rules and Limits
- Operational Notes
Summary of DBMS_SCHEDULER Subprograms

Using DBMS_SCHEDULER

This section contains topics which relate to using the DBMS_SCHEDULER package.

Rules and Limits
Operational Notes

Rules and Limits

The following rules apply when using the DBMS_SCHEDULER package:

Only SYS can do anything in SYS schema.
Several of the procedures accept comma-delimited lists of object names. When a list of names is provided, the Scheduler will stop executing the list on the very first object that returns an error. This means that the Scheduler will not perform the task on the objects in the list after the one that caused the error. For example, consider the statement DBMS_SCHEDULER.STOP_JOB ('job1, job2, job3, sys.jobclass1, sys.jobclass2, sys.jobclass3'); If job3 could not be stopped, then job1 and job2 will be stopped, but the jobs in jobclass1, jobclass2, and jobclass3 will not be stopped.
Performing an action on an object that does not exist returns a PL/SQL exception stating that the object does not exist.

Operational Notes

The Scheduler uses a rich calendaring syntax to enable you to define repeating schedules, such as "every Tuesday and Friday at 4:00 p.m." or "the second Wednesday of every month." This calendaring syntax is used in calendaring expressions in the repeat_interval argument of a number of package subprograms. Evaluating a calendaring expression results in a set of discrete timestamps.

See Oracle Database Administrator's Guide for examples of the calendaring syntax.

Calendaring Syntax

The calendaring syntax is as follows:

repeat_interval = regular_schedule | combined_schedule
 
regular_schedule = frequency_clause
[";" interval_clause] [";" bymonth_clause] [";" byweekno_clause]
[";" byyearday_clause] [";" bydate_clause] [";" bymonthday_clause]
[";" byday_clause] [";" byhour_clause] [";" byminute_clause]
[";" bysecond_clause] [";" bysetpos_clause] [";" include_clause]
[";" exclude_clause] [";" intersect_clause][";" periods_clause]
[";" byperiod_clause]
 
combined_schedule = schedule_list [";" include_clause]
[";" exclude_clause] [";" intersect_clause]

frequency_clause = "FREQ" "=" ( predefined_frequency | user_defined_frequency )
predefined_frequency = "YEARLY" | "MONTHLY" | "WEEKLY" | "DAILY" | 
   "HOURLY" | "MINUTELY" | "SECONDLY"
user_defined_frequency = named_schedule

interval_clause = "INTERVAL" "=" intervalnum
   intervalnum = 1 through 99
bymonth_clause = "BYMONTH" "=" monthlist
   monthlist = monthday ( "," monthday)*
   month = numeric_month | char_month
   numeric_month = 1 | 2 | 3 ...  12
   char_month = "JAN" | "FEB" | "MAR" | "APR" | "MAY" | "JUN" |
   "JUL" | "AUG" | "SEP" | "OCT" | "NOV" | "DEC"
byweekno_clause = "BYWEEKNO" "=" weeknumber_list
   weeknumber_list = weeknumber ( "," weeknumber)*
   weeknumber = [minus] weekno
   weekno = 1 through 53
byyearday_clause = "BYYEARDAY" "=" yearday_list
   yearday_list = yearday ( "," yearday)*
   yearday = [minus] yeardaynum
   yeardaynum = 1 through 366
bydate_clause = "BYDATE" "=" date_list
   date_list = date ( "," date)*
   date = [YYYY]MMDD [ offset | span ]
bymonthday_clause = "BYMONTHDAY" "=" monthday_list
   monthday_list = monthday ( "," monthday)*
   monthday = [minus] monthdaynum
   monthdaynum = 1 through 31
byday_clause = "BYDAY" "=" byday_list
   byday_list = byday ( "," byday)*
   byday = [weekdaynum] day
   weekdaynum = [minus] daynum
   daynum = 1 through 53 /* if frequency is yearly */
   daynum = 1 through 5  /* if frequency is monthly */
   day = "MON" | "TUE" | "WED" | "THU" | "FRI" | "SAT" | "SUN"
byhour_clause = "BYHOUR" "=" hour_list
   hour_list = hour ( "," hour)*
   hour = 0 through 23
byminute_clause = "BYMINUTE" "=" minute_list
   minute_list = minute ( "," minute)*
   minute = 0 through 59
bysecond_clause = "BYSECOND" "=" second_list
   second_list = second ( "," second)*
   second = 0 through 59
bysetpos_clause = "BYSETPOS" "=" setpos_list
   setpos_list = setpos ("," setpos)*
   setpos = [minus] setpos_num
   setpos_num = 1 through 9999

include_clause = "INCLUDE" "=" schedule_list
exclude_clause = "EXCLUDE" "=" schedule_list
intersect_clause = "INTERSECT" "=" schedule_list
schedule_list = schedule_clause ("," schedule_clause)*
schedule_clause = named_schedule [ offset ]
named_schedule = [schema "."] schedule
periods_clause = "PERIODS" "=" periodnum
byperiod_clause = "BYPERIOD" "=" period_list
period_list = periodnum ("," periodnum)*
periodnum = 1 through 100

offset = ("+" | "-") ["OFFSET:"] duration_val
span = ("+" | "-" | "^") "SPAN:" duration_val
duration_val = dur-weeks | dur_days
dur_weeks = numofweeks "W"
dur_days = numofdays "D"
numofweeks = 1 through 53
numofdays = 1 through 376
minus = "-"

In calendaring syntax, * means 0 or more.

Table 93-1 Values for repeat_interval

Name	Description
`FREQ`	This specifies the type of recurrence. It must be specified. The possible predefined frequency values are YEARLY, MONTHLY, WEEKLY, DAILY, HOURLY, MINUTELY, and SECONDLY. Alternatively, specifies an existing schedule to use as a user-defined frequency.
`INTERVAL`	This specifies a positive integer representing how often the recurrence repeats. The default is 1, which means every second for secondly, every day for daily, and so on. The maximum value is 999.
`BYMONTH`	This specifies which month or months you want the job to execute in. You can use numbers such as 1 for January and 3 for March, as well as three-letter abbreviations such as FEB for February and JUL for July.
`BYWEEKNO`	This specifies the week of the year as a number. It follows ISO-8601, which defines the week as starting with Monday and ending with Sunday; and the first week of a year as the first week, which is mostly within the Gregorian year. That last definition is equivalent to the following two variants: the week that contains the first Thursday of the Gregorian year; and the week containing January 4th. The ISO-8601 week numbers are integers from 1 to 52 or 53; parts of week 1 may be in the previous calendar year; parts of week 52 may be in the following calendar year; and if a year has a week 53, parts of it must be in the following calendar year. As an example, in the year 1998 the ISO week 1 began on Monday December 29th, 1997; and the last ISO week (week 53) ended on Sunday January 3rd, 1999. So December 29th, 1997, is in the ISO week 1998-01; and January 1st, 1999, is in the ISO week 1998-53. `byweekno` is only valid for YEARLY. Examples of invalid specifications are `"FREQ=YEARLY; BYWEEKNO=1; BYMONTH=12"` and `"FREQ=YEARLY;BYWEEKNO=53;BYMONTH=1"`.
`BYYEARDAY`	This specifies the day of the year as a number. Valid values are 1 to 366. An example is 69, which is March 10 (31 for January, 28 for February, and 10 for March). 69 evaluates to March 10 for non-leap years and March 9 in leap years. -2 will always evaluate to December 30th independent of whether it is a leap year.
`BYDATE`	This specifies a list of dates, where each date is of the form `[YYYY]MMDD`. A list of consecutive dates can be generated by using the `SPAN` modifier, and a date can be adjusted with the `OFFSET` modifier. An example of a simple `BYDATE` clause is the following: `BYDATE=0115,0315,0615,0915,1215,20060115` The following `SPAN` example is equivalent to `BYDATE=0110,0111,0112,0113,0114`, which is a span of 5 days starting at 1/10: `BYDATE=0110+SPAN:5D` The plus sign in front of the `SPAN` keyword indicates a span starting at the supplied date. The minus sign indicates a span ending at the supplied date, and the "^" sign indicates a span of n days or weeks centered around the supplied date. If n is an even number, it is adjusted up to the next odd number. Offsets adjust the supplied date by adding or subtracting n days or weeks. `BYDATE=0205-OFFSET:2W` is equivalent to `BYDATE=0205-14D` (the `OFFSET:` keyword is optional), which is also equivalent to `BYDATE=0122`.
`BYMONTHDAY`	This specifies the day of the month as a number. Valid values are 1 to 31. An example is 10, which means the 10th day of the selected month. You can use the minus sign (-) to count backward from the last day, so, for example, `BYMONTHDAY=-1` means the last day of the month and `BYMONTHDAY=-2` means the next to last day of the month.
`BYDAY`	This specifies the day of the week from Monday to Sunday in the form MON, TUE, and so on. Using numbers, you can specify the 26th Friday of the year, if using a YEARLY frequency, or the 4th THU of the month, using a MONTHLY frequency. Using the minus sign, you can say the second to last Friday of the month. For example, `-1 FRI` is the last Friday of the month.
`BYHOUR`	This specifies the hour on which the job is to run. Valid values are 0 to 23. As an example, 10 means 10 a.m.
`BYMINUTE`	This specifies the minute on which the job is to run. Valid values are 0 to 59. As an example, 45 means 45 minutes past the chosen hour.
`BYSECOND`	This specifies the second on which the job is to run. Valid values are 0 to 59. As an example, 30 means 30 seconds past the chosen minute.
`BYSETPOS`	This selects one or more items by position in the list of timestamps that result after the whole calendaring expression is evaluated. It is useful for requirements such as running a job on the last workday of the month. Rather than attempting to express this with the other `BY` clauses, you can code the calendaring expression to evaluate to a list of every workday of the month, and then add the `BYSETPOS` clause to select only the last item of that list. Assuming that workdays are Monday through Friday, the syntax would then be: FREQ=MONTHLY; BYDAY=MON,TUE,WED,THU,FRI; BYSETPOS=-1 Valid values are 1 through 9999. A negative number selects an item from the end of the list (-1 is the last item, -2 is the next to last item, and so on) and a positive number selects from the front of the list. The `BYSETPOS` clause is always evaluated last. `BYSETPOS` is only supported with the `MONTHLY` and `YEARLY` frequencies. The `BYSETPOS` clause is applied to the list of timestamps once per frequency period. For example, when the frequency is defined as `MONTHLY`, the Scheduler determines all valid timestamps for the month, orders that list, and then applies the `BYSETPOS` clause. The Scheduler then moves on to the next month and repeats the procedure. Assuming a start date of Jun 10, 2004, the example evaluates to: Jun 30, Jul 30, Aug 31, Sep 30, Oct 29, and so on.
`INCLUDE`	This includes one or more named schedules in the calendaring expression. That is, the set of timestamps defined by each included named schedule is added to the results of the calendaring expression. If an identical timestamp is contributed by both an included schedule and the calendaring expression, it is included in the resulting set of timestamps only once. The named schedules must have been defined with the `CREATE_SCHEDULE` procedure.
`EXCLUDE`	This excludes one or more named schedules from the calendaring expression. That is, the set of timestamps defined by each excluded named schedule is removed from the results of the calendaring expression. The named schedules must have been defined with the `CREATE_SCHEDULE` procedure.
`INTERSECT`	This specifies an intersection between the calendaring expression results and the set of timestamps defined by one or more named schedules. Only the timestamps that appear both in the calendaring expression and in one of the named schedules are included in the resulting set of timestamps. For example, assume that the named schedule `last_sat` indicates the last Saturday in every month, and that for the year 2005, the only months where the last day of the month is also a Saturday are April and December. Assume also that the named schedule `end_qtr` indicates the last day of each quarter in 2005: 3/31/2005, 6/30/2005, 9/30/2005, 12/31/2005 The following calendaring expression results in the these dates: 3/31/2005, 4/30/2005, 6/30/2005, 9/30/2005, 12/31/2005 FREQ=MONTHLY; BYMONTHDAY=-1; INTERSECT=last_sat,end_qtr In this example, the terms `FREQ=MONTHLY; BYMONTHDAY=-1` indicate the last day of each month.
`PERIODS`	This identifies the number of periods that together form one cycle of a user defined frequency. It is used in the `repeat_interval` expression of the schedule that defines the user defined frequency. It is mandatory when the `repeat_interval` expression in the main schedule contains a `BYPERIOD` clause. The following example defines the quarters of a fiscal year. FREQ=YEARLY;BYDATE=0301,0601,0901,1201;PERIODS=4
`BYPERIOD`	This selects periods from a user defined frequency. For example, if a main schedule names a user defined frequency schedule that defines the fiscal quarters shown in the previous example, the clause `BYPERIOD=2,4` in the main schedule selects the 2nd and 4th fiscal quarters.

Combining Schedules

There are two ways to combine schedules:

Using a combined schedule expression, which is a list of individual schedules

For example, to create a schedule for all company holidays, you provide a list of individual schedules, where each schedule in the list defines a single holiday. The Scheduler evaluates each individual schedule, and then returns a union of the timestamps returned by each individual schedule. You can follow the initial list of individual schedules with include, exclude, and intersect clauses to create more complex combinations.
Embedding other schedules into the main schedule using include, exclude, and intersect clauses

With this method, the embedded schedules inherit certain attributes from the main schedule.
- Timestamps generated by the INCLUDE clause that fall into periods that are skipped by the main schedule are ignored. This is the case when the main schedule skips periods due to the INTERVAL clause, the BYPERIOD clause, or the BYMONTH clause for freq=monthly.
- Days that are added by the INCLUDE clause follow the hourly/minutely/secondly execution pattern of the main schedule.
- When the INCLUDE clause is present, no date-specific defaults are retrieved from the start date (but time-specific defaults can be). (See "Start Dates and Repeat Intervals", later in this section.) For example, a repeat_interval of FREQ=MONTHLY;INCLUDE=HOLIDAY executes only on holidays and not on the month/day defaults retrieved from the start date.
The following is an example:
```
BEGIN
dbms_scheduler.create_schedule('embed_sched', repeat_interval =>
  'FREQ=YEARLY;BYDATE=0130,0220,0725');
dbms_scheduler.create_schedule('main_sched', repeat_interval =>
  'FREQ=MONTHLY;INTERVAL=2;BYMONTHDAY=15;BYHOUR=9,17;INCLUDE=embed_sched');
END;
/
```
In this example, the dates 1/30, 2/20, and 7/25 are added to the main schedule. However, the Scheduler does not include dates that fall in months that are skipped by the INTERVAL clause. If the start date of the main schedule is 1/1/2005, then 2/20 isn't added. On the dates that are added, the embedded schedule follows the execution pattern of the main schedule: jobs are executed at 9:00 a.m. and 5:00 p.m. on 1/30 and 7/25. If the embedded schedule does not itself have a start date, it inherits the start date from the main schedule.

User Defined Frequencies

Instead of using predefined frequencies like DAILY, WEEKLY, MONTHLY, and so on, you can create your own frequencies by creating a schedule that returns the start date of each period. For example, the following repeat_interval expression is used in a schedule named fiscal_year that defines the start of each quarter in a fiscal year:

FREQ=YEARLY;BYDATE=0301,0601,0901,1201;PERIODS=4

To return the last Wednesday of every quarter, you create a schedule (the "main schedule") that uses the fiscal_year schedule as a user defined frequency:

FREQ=fiscal_year;BYDAY=-1WED

Periods in a user defined frequency do not have to be equal in length. In the main schedule, the BYSETPOS clause and numbered weekdays are recalculated based on the size of each period. To select dates in specific periods, you must use the BYPERIOD clause in the main schedule. To enable this, the schedule that is used as the user defined frequency must include a PERIODS clause, and it must set its start date appropriately. The first date returned by this schedule is used as the starting point of period 1.

As another example, assuming work days are Monday through Friday, to get the last work day of the 2nd and 4th quarters of the fiscal year, the repeat_interval clause in the main schedule is the following:

FREQ=fiscal_year;BYDAY=MON,TUE,WED,THU,FRI;BYPERIOD=2,4;BYSETPOS=-1

Start Dates and Repeat Intervals

The Scheduler retrieves the date and time from the job or schedule start date and incorporates them as defaults into the repeat_interval. For example, if the specified frequency is yearly and there is no BYMONTH or BYMONTHDAY clause in the repeat interval, the month and day on which to run the job are retrieved from the start date. Similarly, if frequency is monthly but there is no BYMONTHDAY clause in the repeat interval, the day of the month on which to run the job is retrieved from the start date. If present, BYHOUR, BYMINUTE, and BYSECOND defaults are also retrieved from the start date, and used if those clauses are not specified. Note that if the INCLUDE, EXCLUDE, or INTERSECT clauses are present, no date-related defaults are retrieved from the start date, but time-related defaults are.The following are some examples:

start_date:      4/15/05 9:00:00
repeat_interval: freq=yearly

is expanded internally to:

freq=yearly;bymonth=4;bymonthday=15;byhour=9;byminute=0;bysecond=0

The preceding schedule executes on 04/15/05 9:00:00, 04/15/06 9:00:00, 04/15/07 9:00:00, and so on.

For the next example, assume that schedule S1 has a repeat_interval of FREQ=YEARLY;BYDATE=0701.

start_date:      01/20/05 9:00:00
repeat_interval: freq=yearly;include=S1

is expanded internally to:

freq=yearly;byhour=9;byminute=0;bysecond=0;include=S1

Because an INCLUDE clause is present, date-related information is not retrieved from the start date. However, time-specific information is, so the preceding schedule executes on 07/01/05 9:00:00, 07/01/06 9:00:00, 07/01/08 9:00:00, and so on.

General Rules

When using a calendaring expression, consider the following rules:

For a regular schedule (as opposed to a combined schedule), the calendar string must start with the frequency clause. All other clauses are optional and can be put in any order.
All clauses are separated by a semi-colon, and each clause can be present at most once, with the exception of the include, exclude, and intersect clauses.
Spaces are allowed between syntax elements and the strings are case insensitive.
The list of values for a specific BY clause do not need to be ordered.
When not enough BY clauses are present to determine what the next date is, this information is retrieved from the start date. For example, "FREQ=YEARLY" with a start date of 02/15/2003 becomes "FREQ=YEARLY;BYMONTH=FEB; BYMONTHDAY=15", which means every year on the 15th of February.

"FREQ=YEARLY;BYMONTH=JAN,JUL" with start date 01/21/2003 becomes "FREQ=YEARLY;BYMONTH=JAN,JUL;BYMONTHDAY=21", which means every year on January 21 and July 21.
The byweekno clause is only allowed if the frequency is YEARLY. It cannot be used with other frequencies. When it is present, it will return all days in that week number. If you want to limit it to specific days within the week, you have to add a BYDAY clause. For example, "FREQ=YEARLY;BYWEEKNO=2" with a start date of 01/01/2003 will return:
```
01/06/2003, 01/07/2003, 01/08/2003, 01/09/2003, 01/10/2003, 01/11/2003, 01/12/2003, 01/05/2004, 01/06/2004, 01/07/2004, .... and so on.
```
Note that when the byweekno clause is used, it is possible that the dates returned are from a year other than the current year. For example, if returning dates for the year 2004 and the calendar string is "FREQ=YEARLY;BYWEEKNO=1,53" for the specified week numbers in 2004, it will return the dates:
```
12/29/03, 12/30/03, 12/31/03, 01/01/04, 01/02/04, 01/03/04, 01/04/04, 12/27/04, 12/28/04, 12/29/04, 12/30/04, 12/31/04, 01/01/05, 01/02/05
```
For those BY clauses that do not have a consistent range of values, you can count backward by putting a "-" in front of the numeric value. For example, specifying BYMONTHDAY=31 will not give you the last day of every month, because not every month has 31 days. Instead, BYMONTHDAY=-1 will give you the last day of the month.

This is not supported for BY clauses that are fixed in size. In other words, BYMONTH, BYHOUR, BYMINUTE, and BYSECOND are not supported.
The basic values for the BYDAY clause are the days of the week. When the frequency is YEARLY, or MONTHLY, you are allowed to specify a positive or negative number in front of each day of the week. In the case of YEARLY, BYDAY=40MON, indicates the 40th Monday of the year. In the case of MONTHLY, BYDAY=-2SAT, indicates the second to last Saturday of the month.

Note that positive or negative numbers in front of the weekdays are not supported for other frequencies and that in the case of yearly, the number ranges from -53 ... -1, 1 ... 53, whereas for the monthly frequency it is limited to -5 ... -1, 1... 5.

If no number is present in front of the weekday it specifies, every occurrence of that weekday in the specified frequency.
The first day of the week is Monday.
Repeating jobs with frequencies smaller than daily follow their frequencies exactly across daylight savings adjustments. For example, suppose that a job is scheduled to repeat every 3 hours, the clock is moved forward from 1:00 a.m. to 2:00 a.m., and the last time the job ran was midnight. Its next scheduled time will be 4:00 a.m. Thus, the 3 hour period between subsequent job runs is retained. The same applies when the clock is moved back. This behavior is not the case for repeating jobs that have frequencies of daily or larger. For example, if a repeating job is supposed to be executed on a daily basis at midnight, it will continue to run at midnight if the clock is moved forward or backward. When the execution time of such a daily (or larger frequency) job happens to fall inside a window where the clock is moved forward, the job executes at the end of the window.
The calendaring syntax does not allow you to specify a time zone. Instead the Scheduler retrieves the time zone from the start_date argument. If jobs must follow daylight savings adjustments you must make sure that you specify a region name for the time zone of the start_date. For example specifying the start_date time zone as 'US/Eastern' in New York will make sure that daylight saving adjustments are automatically applied. If instead the time zone of the start_date is set to an absolute offset, such as '-5:00', daylight savings adjustments are not followed and your job execution will be off by an hour half of the year.
When start_date is NULL, the Scheduler will determine the time zone for the repeat interval as follows:
1. It will check whether the session time zone is a region name. The session time zone can be set by either:
  - Issuing an ALTER SESSION statement, for example:
```
SQL> ALTER SESSION SET time_zone = 'Asia/Shanghai';
```
  - Setting the ORA_SDTZ environment variable.
2. If the session time zone is an absolute offset instead of a region name, the Scheduler will use the value of the DEFAULT_TIMEZONE Scheduler attribute. For more information, see the SET_SCHEDULER_ATTRIBUTE Procedure.
3. If the DEFAULT_TIMEZONE attribute is NULL, the Scheduler will use the time zone of systimestamp when the job or window is enabled.

BYSETPOS Clause Rules

The BYSETPOS clause is the last clause to be evaluated. It is processed after all other BY clauses and the INCLUDE, EXCLUDE and INTERSECT clauses have been evaluated.
The INTERVAL clause does not change the size of the period to which the BYSETPOS clause is applied. For example, when the frequency is set to monthly and interval is set to 3, the list of timestamps to which BYSETPOS is applied is generated from a month, not a quarter. The only impact of the INTERVAL clause is to cause months to be skipped. However, you can still select the second to last workday of the quarter like this:
```
FREQ=MONTHLY;INTERVAL=3;BYDAY=MON,TUE,WED,THU,FRI;BYSETPOS=-2
```
provided that you set the start date in the right month. This example returns the next to last workday of a month, and repeats once a quarter.
To get consistent results, the set to which BYSETPOS is applied is determined from the beginning of the frequency period independently of when the evaluation occurs. Whether the Scheduler evaluates
```
FREQ=MONTHLY;BYDAY=MON,TUE,FRI;BYSETPOS=1,3
```
on 01/01/2004 or 01/15/2004, in both cases the expression evaluates to Friday 01/02/2004, and Tuesday 01/06/2004. The only difference is that when the expression is evaluated on 01/15/2004, the Scheduler determines that there are no matches in January because the timestamps found are in the past, and it moves on to the matches in the next month, February.

BYDATE Clause Rules

If dates in the BYDATE clause do not have their optional year component, the job runs on those dates every year.
The job execution times on the included dates are derived from the BY clauses in the calendaring expression. For example, if repeat_interval is defined as
```
freq=daily;byhour=8,13,18;byminute=0;bysecond=0;bydate=0502,0922
```
then the execution times on 05/02 and 09/22 are 8:00 a.m., 1:00 p.m., and 6:00 p.m.

EXCLUDE Clause Rules

Excluded dates without a time component are 24 hour periods. All timestamps that fall on an excluded date are removed. In the following example, jan_fifteen is a named schedule that resolves to the single date of 01/15:
```
freq=monthly;bymonthday=15,30;byhour=8,13,18;byminute=0;bysecond=0;
     exclude=jan_fifteenth
```
In this case, all three instances of the job are removed for 01/15.

OFFSET Rules

You can adjust the dates of individual named schedules by adding positive offsets to them. For example, to execute JOB2 exactly 15 days after every occurrence of JOB1, add +OFFSET:15D to the schedule of JOB1, as follows:
```
BEGIN
dbms_scheduler.create_schedule('job2_schedule', repeat_interval =>
  'job1_schedule+OFFSET:15D');
END;
/
```
Note that negative offsets to named schedules are not supported.

Example: Putting It All Together

This example demonstrates the use of user defined frequencies, spans, offsets, and the BYSETPOS and INCLUDE clauses. (Note that the OFFSET: keyword in an offset clause is optional.)

Many companies in the retail industry share the same fiscal year. The fiscal year starts on the Sunday closest to February 1st, and subsequent quarters start exactly 13 weeks later. The fiscal year schedule for the retail industry can be defined as the following:

begin
 dbms_scheduler.create_schedule('year_start', repeat_interval=>
       'FREQ=YEARLY;BYDATE=0201^SPAN:1W;BYDAY=SUN');
 dbms_scheduler.create_schedule('retail_fiscal_year',
        to_timestamp_tz('15-JAN-2005 12:00:00','DD-MON-YYYY HH24:MI:SS'),
         'year_start,year_start+13w,year_start+26w,year_start+39w;periods=4');
end;
/

The following schedule can be used to execute a job on the 5th day off in the 2nd and the 4th quarters of the retail industry. This assumes that Saturday and Sunday are off days as well as the days in the existing holiday schedule.

begin
 dbms_scheduler.create_schedule('fifth_day_off', repeat_interval=>
  'FREQ=retail_fiscal_year;BYDAY=SAT,SUN;INCLUDE=holiday;
    BYPERIOD=2,4;BYSETPOS=5');
end;
/

Summary of DBMS_SCHEDULER Subprograms

Table 93-2 DBMS_SCHEDULER Package Subprograms

Subprogram	Description
ADD_EVENT_QUEUE_SUBSCRIBER Procedure	Adds a user as a subscriber to the Scheduler event queue `SYS.SCHEDULER$_EVENT_QUEUE`
ADD_WINDOW_GROUP_MEMBER Procedure	Adds a window to an existing window group
ALTER_CHAIN Procedure	Alters specified steps of a chain
ALTER_RUNNING_CHAIN Procedure	Alters specified steps of a running chain
CLOSE_WINDOW Procedure	Closes an open window prematurely
COPY_JOB Procedure	Copies an existing job
CREATE_CHAIN Procedure	Creates a chain, which is a named series of programs that are linked together for a combined objective
CREATE_EVENT_SCHEDULE Procedure	Creates an event schedule, which is a schedule that starts a job based on the detection of an event
CREATE_JOB Procedures	Creates a job
CREATE_JOB_CLASS Procedure	Creates a job class, which provides a way to group jobs for resource allocation and prioritization
CREATE_PROGRAM Procedure	Creates a program
CREATE_SCHEDULE Procedure	Creates a schedule
CREATE_WINDOW Procedures	Creates a window, which provides a way to automatically activate different resource plans at different times
CREATE_WINDOW_GROUP Procedure	Creates a window group
DEFINE_ANYDATA_ARGUMENT Procedure	Defines a program argument whose value is of a complex type and must be passed encapsulated in an `AnyData` object
DEFINE_CHAIN_EVENT_STEP Procedure	Adds or replaces a chain step and associates it with an event schedule or inline event. See also: `DEFINE_CHAIN_STEP`.
DEFINE_CHAIN_RULE Procedure	Adds a rule to an existing chain
DEFINE_CHAIN_STEP Procedure	Defines a chain step, which can be a program or another (nested) chain. See also: `DEFINE_CHAIN_EVENT_STEP`.
DEFINE_METADATA_ARGUMENT Procedure	Defines a special metadata argument for the program. You can retrieve specific metadata through this argument
DEFINE_PROGRAM_ARGUMENT Procedures	Defines a program argument whose value can be passed as a string literal to the program
DISABLE Procedure	Disables a program, job, chain, window, or window group
DROP_CHAIN Procedure	Drops an existing chain
DROP_CHAIN_RULE Procedure	Removes a rule from an existing chain
DROP_CHAIN_STEP Procedure	Drops a chain step
DROP_JOB Procedure	Drops a job or all jobs in a job class
DROP_JOB_CLASS Procedure	Drops a job class
DROP_PROGRAM Procedure	Drops a program
DROP_PROGRAM_ARGUMENT Procedures	Drops a program argument
DROP_SCHEDULE Procedure	Drops a schedule
DROP_WINDOW Procedure	Drops a window
DROP_WINDOW_GROUP Procedure	Drops a window group
ENABLE Procedure	Enables a program, job, chain, window, or window group
EVALUATE_CALENDAR_STRING Procedure	Evaluates the calendar string and tells you what the next execution date of a job or window will be
EVALUATE_RUNNING_CHAIN Procedure	Forces reevaluation of the rules of a running chain to trigger any rules for which the conditions have been satisfied
GENERATE_JOB_NAME Function	Generates a unique name for a job. This enables you to identify jobs by adding a prefix, so, for example, Sally's jobs would be named `sally1`, `sally2`, and so on
GET_ATTRIBUTE Procedure	Retrieves the value of an attribute of an object
GET_SCHEDULER_ATTRIBUTE Procedure	Retrieves the value of a Scheduler attribute
OPEN_WINDOW Procedure	Opens a window prematurely. The window is opened immediately for the duration
PURGE_LOG Procedure	Purges specific rows from the job and window logs
REMOVE_EVENT_QUEUE_SUBSCRIBER Procedure	Unsubscribes a user from the Scheduler event queue `SYS.SCHEDULER$_EVENT_QUEUE`
REMOVE_WINDOW_GROUP_MEMBER Procedure	Removes a window from an existing window group. This fails if the specified window is not a member of the given group
RESET_JOB_ARGUMENT_VALUE Procedures	Resets the current value assigned to an argument defined with the associated program
RUN_CHAIN Procedures	Immediately runs a chain by creating a run-once job
RUN_JOB Procedure	Runs a job immediately
SET_ATTRIBUTE Procedure	Changes an attribute of a job, schedule, or other Scheduler object
SET_ATTRIBUTE_NULL Procedure	Changes an attribute of an object to `NULL`
SET_JOB_ANYDATA_VALUE Procedures	Sets the value of a job argument encapsulated in an `AnyData` object
SET_JOB_ARGUMENT_VALUE Procedures	Sets the value of a job argument
SET_SCHEDULER_ATTRIBUTE Procedure	Sets the value of a Scheduler attribute
STOP_JOB Procedure	Stops a currently running job or all jobs in a job class

ADD_EVENT_QUEUE_SUBSCRIBER Procedure

This procedure adds a user as a subscriber to the Scheduler event queue SYS.SCHEDULER$_EVENT_QUEUE, and grants the user permission to dequeue from this queue using the designated agent.

Syntax

DBMS_SCHEDULER.ADD_EVENT_QUEUE_SUBSCRIBER (
   subscriber_name         IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-3 ADD_EVENT_QUEUE_SUBSCRIBER Procedure Parameters

Parameter	Description
`subscriber_name`	Name of the Oracle Streams Advanced Queuing (AQ) agent to be used to subscribe to the Scheduler event queue. If `NULL`, an agent is created and assigned the user name of the calling user.

Usage Notes

The subscription is rule-based. The rule permits the user to see only events raised by jobs that the user owns, and filters out all other messages. If an AQ agent with the same name already exists, an error is raised.

ADD_WINDOW_GROUP_MEMBER Procedure

This procedure adds one or more windows to an existing window group.

Syntax

DBMS_SCHEDULER.ADD_WINDOW_GROUP_MEMBER (
   group_name              IN VARCHAR2,
   window_list             IN VARCHAR2);

Parameters

Table 93-4 ADD_WINDOW_GROUP_MEMBER Procedure Parameters

Parameter	Description
`group_name`	The name of the window group
`window_list`	The name of the window or windows

Usage Notes

If an already open window is added to a window group, the Scheduler will not pick up jobs that point to this window group until the next window in the window group opens.

Adding a window to a group requires the MANAGE SCHEDULER privilege.

Note that a window group cannot be a member of another window group.

ALTER_CHAIN Procedure

This procedure alters specified steps of a chain. This affects all future runs of the specified steps.

Syntax

DBMS_SCHEDULER.ALTER_CHAIN (
   chain_name              IN VARCHAR2,
   step_name               IN VARCHAR2,
   attribute               IN VARCHAR2,
   value                   IN BOOLEAN);

Parameters

Table 93-5 ALTER_CHAIN Procedure Parameters

Parameter	Description
`chain_name`	The name of the chain to alter
`step_name`	The name of the step or a comma-separated list of steps to alter. This cannot be `NULL`.
`attribute`	The attribute of the steps to change. This must be one of: '`PAUSE`', '`SKIP`', or '`RESTART_ON_RECOVERY`' '`PAUSE`'—If the `PAUSE` attribute is set `TRUE` for a step, after the step has run, its state will be changed to `PAUSED` (and the `completed` attribute will remain `FALSE`). If `PAUSE` is reset to `FALSE` for a paused chain step (using `ALTER_RUNNING_CHAIN`), the state will be set to its completion state (`SUCCEEDED`, `FAILED`, or `STOPPED`) and the `completed` attribute will be set to `TRUE`. Setting `PAUSE` will have no effect on steps that have already run. This allows execution of a chain to be suspended after the execution of certain steps. '`SKIP`'—If the `SKIP` attribute is set `TRUE` for a step, when the step condition is met, instead of being run, the step is treated as if it has immediately succeeded. Setting `SKIP` to `TRUE` has no effect for a step that is running, scheduled to run after a delay, or has already run. If `SKIP` is set `TRUE` for a step that `PAUSE` is also set for, when the step condition is met, the step immediately changes to state `PAUSED`. '`RESTART_ON_RECOVERY`'—If the `RESTART_ON_RECOVERY` attribute is set to `TRUE` for a step, then if the step is stopped by a database shutdown, it is restarted when the database is recovered. If this attribute is set to `FALSE`, then if the step is stopped by a database shutdown, the step is marked as stopped when the database is recovered and the chain continues.
`value`	The value to set for the attribute. This must be one of: `TRUE`, `FALSE`.

Usage Notes

Altering a chain requires ALTER privileges on the chain either by being the owner of the chain, or by having the ALTER object privilege on the chain or by having the CREATE ANY JOB system privilege.

ALTER_RUNNING_CHAIN Procedure

This procedure alters specified steps of a running chain. This will affect only steps of this running instance of the chain.

Syntax

DBMS_SCHEDULER.ALTER_RUNNING_CHAIN (
   job_name                IN VARCHAR2,
   step_name               IN VARCHAR2,
   attribute               IN VARCHAR2,
   value                   IN [BOOLEAN|VARCHAR2]);

Parameters

Table 93-6 ALTER_RUNNING_CHAIN Procedure Parameters

Parameter	Description
`job_name`	The name of the job that is running the chain
`step_name`	The name of the step or a comma-separated list of steps to alter. If this is set to `NULL` and attribute is `PAUSE` or `SKIP`, then all steps of the running chain will be altered.
`attribute`	The attribute of the steps to change. This must be one of: '`PAUSE`', '`SKIP`', '`RESTART_ON_RECOVERY`', or '`STATE`'. '`PAUSE`'—If the `PAUSE` attribute is set `TRUE` for a step, after the step has run, its state will be changed to `PAUSED` (and the `completed` attribute will remain false). If `PAUSE` is reset to `FALSE` for a paused chain step (using `ALTER_RUNNING_CHAIN`), the state will be set to its completion state (`SUCCEEDED`, `FAILED`, or `STOPPED`) and the `completed` attribute will be set to `TRUE`. Setting `PAUSE` will have no effect on steps that have already run. This allows execution of a chain to be suspended after the execution of certain steps. If `step_name` is set to `NULL`, `PAUSE` will be set to `TRUE` for all steps of this running chain. '`SKIP`'—If the `SKIP` attribute is set to `TRUE` for a step, when the step condition is met, instead of being run, the step is treated as if it has immediately succeeded. Setting `SKIP` to `TRUE` has no effect for a step that is running, scheduled to run after a delay, or has already run. If `step_name` is set to `NULL`, `SKIP` will be set `TRUE` for all steps of this running chain. If `SKIP` is set `TRUE` for a step that `PAUSE` is also set for, when the step condition is met the step will immediately change to state `PAUSED`. '`RESTART_ON_RECOVERY`'—If the `RESTART_ON_RECOVERY` attribute is set to `TRUE` for a step, then if the step is stopped by a database shutdown, it is restarted when the database is recovered. If this attribute is set to `FALSE`, then if the step is stopped by a database shutdown, the step is marked as stopped when the database is recovered and the chain continues. '`STATE`'—This changes the state of the steps. The state can only be changed if the step is not running. The state can only be changed to one of the following: 'NOT_STARTED', 'SUCCEEDED', 'FAILED error_code' If the state is being changed to `FAILED`, an error code must be included (this must be a positive integer).
`value`	The value to set for the attribute. This must be one of: `TRUE`, `FALSE`, '`NOT_STARTED`', '`SUCCEEDED`', or '`FAILED` `error_code`'

Usage Notes

Altering a running chain requires alter privileges on the job which is running (either by being the owner, or by having ALTER privileges on the job or by having the CREATE ANY JOB system privilege).

CLOSE_WINDOW Procedure

This procedure closes an open window prematurely. A closed window means that it is no longer in effect. When a window is closed, the Scheduler will switch the resource plan to the one that was in effect outside the window or in the case of overlapping windows to another window.

Syntax

DBMS_SCHEDULER.CLOSE_WINDOW (
   window_name             IN VARCHAR2);

Parameters

Table 93-7 CLOSE_WINDOW Procedure Parameters

Parameter	Description
`window_name`	The name of the window

Usage Notes

If you try to close a window that does not exist or is not open, an error is generated.

A job that is running will not stop when the window it is running in closes unless the attribute stop_on_window_close was set to TRUE for the job. However, the resources allocated to the job may change because the resource plan may change.

When a running job has a window group as its schedule, the job will not be stopped when its window is closed if another window that is also a member of the same window group then becomes active. This is the case even if the job has the attribute stop_on_window_close set to TRUE.

Closing a window requires the MANAGE SCHEDULER privilege.

COPY_JOB Procedure

This procedure copies all attributes of an existing job to a new job. The new job is created disabled, while the state of the existing job is unaltered.

Syntax

DBMS_SCHEDULER.COPY_JOB (
   old_job                IN VARCHAR2,
   new_job                IN VARCHAR2);

Parameters

Table 93-8 COPY_JOB Procedure Parameters

Parameter	Description
`old_job`	The name of the existing job
`new_job`	The name of the new job

Usage Notes

Copying a job requires privileges to create a job in the schema of the new job (the CREATE JOB system privilege if it is in the user's own schema, and the CREATE ANY JOB system privilege otherwise). If the old job is not in the user's own schema, then he needs to additionally have ALTER privileges on the old job or the CREATE ANY JOB system privilege.

CREATE_CHAIN Procedure

This procedure creates a new chain. The chain name can be optionally qualified with a schema name (for example, myschema.myname).

A chain is always created disabled and must be enabled with the ENABLE Procedure before it can be used.

Syntax

DBMS_SCHEDULER.CREATE_CHAIN (
   chain_name              IN VARCHAR2,
   rule_set_name           IN VARCHAR2 DEFAULT NULL,
   evaluation_interval     IN INTERVAL DAY TO SECOND DEFAULT NULL,
   comments                IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-9 CREATE_CHAIN Procedure Parameters

Parameter	Description
`chain_name`	The name of the new chain, which can optionally be qualified with a schema. This must be unique in the SQL namespace, so there must not already be a table or other object with this name and schema.
`rule_set_name`	In the normal case, no rule set should be passed in. The Scheduler will automatically create a rule set and associated empty evaluation context. You then use `DEFINE_CHAIN_RULE` to add rules and `DROP_CHAIN_RULE` to remove them. Advanced users can create a rule set that describes their chain dependencies and pass it in here. This allows greater flexibility in defining rules. For example, conditions can refer to external variables, and tables can be exposed through the evaluation context. If you pass in a rule set, you must ensure that it is in the format of a chain rule set. (For example, all steps must be listed as variables in the evaluation context). If no rule set is passed in, the rule set created will be of the form `SCHED_RULESET${N}` and the evaluation context created will be of the form `SCHED_EVCTX${N}` See Oracle Streams Concepts and Administration for information on rules and rule sets.
`evaluation_interval`	If this is `NULL`, reevaluation of the rules of a running chain are performed only when the job starts and when a step completes. A non-`NULL` value causes rule evaluations to also occur periodically at the specified interval. Because evaluation may be CPU-intensive, this should be conservatively set to the highest possible value or left at `NULL` if possible. `evaluation_interval` cannot be less than a minute or greater than a day.
`comments`	An optional comment describing the purpose of the chain

Usage Notes

Creating a chain in one's own schema requires the CREATE JOB system privilege. Creating a chain in a different schema requires the CREATE ANY JOB system privilege. If no rule_set_name is given, a rule set and evaluation context will be created in the schema that the chain is being created in, so the user will need to have the privileges required to create these objects. See the DBMS_RULE_ADM.CREATE_RULE_SET and DBMS_RULE_ADM.CREATE_EVALUATION_CONTEXT procedures for more information.

CREATE_EVENT_SCHEDULE Procedure

This procedure creates an event schedule, which is used to start a job when a particular event is raised.

Syntax

DBMS_SCHEDULER.CREATE_EVENT_SCHEDULE (
   schedule_name           IN VARCHAR2,
   start_date              IN TIMESTAMP WITH TIME ZONE DEFAULT NULL,
   event_condition         IN VARCHAR2,
   queue_spec              IN VARCHAR2,
   end_date                IN TIMESTAMP WITH TIME ZONE DEFAULT NULL,
   comments                IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-10 CREATE_EVENT_SCHEDULE Parameters

Parameter	Description
`schedule_name`	This.attribute specifies a unique identifier for the schedule. The name has to be unique in the SQL namespace. For example, a schedule cannot have the same name as a table in a schema. If no name is specified, then an error occurs.
`start_date`	This attribute specifies the date on which this schedule becomes valid. Occurrences of the event before this date are ignored in the context of this schedule.
`event_condition`	This is a conditional expression based on the columns of the event source queue table. The expression must have the syntax of an Advanced Queuing rule. Accordingly, you can include user data properties in the expression provided that the message payload is an object type, and that you prefix object attributes in the expression with `tab.user_data`. For more information on rules, see the `DBMS_AQADM`.`ADD_SUBSCRIBER` procedure.
`queue_spec`	This argument specifies the queue into which events that start this particular job will be enqueued (the source queue). If the source queue is a secure queue, the `queue_spec` argument is a string containing a pair of values of the form queue_name, agent name. For non-secure queues, only the queue name need be provided. If a fully qualified queue name is not provided, the queue is assumed to be in the job owner's schema. In the case of secure queues, the agent name provided should belong to a valid agent that is currently subscribed to the queue.
`end_date`	The date after which jobs will not run and windows will not open. An event schedule that has no `end_date` is valid forever. `end_date` has to be after the `start_date`. If this is not the case, then an error will be generated when the schedule is created.
`comments`	This attribute specifies an optional comment about the schedule. By default, this attribute is `NULL`.

Usage Notes

This procedure requires the CREATE JOB privilege to create a schedule in one's own schema or the CREATE ANY JOB privilege to create a schedule in someone else's schema by specifying schema.schedule_name. Once a schedule has been created, it can be used by other users. The schedule is created with access to PUBLIC. Therefore, there is no need to explicitly grant access to the schedule.

CREATE_JOB Procedures

This procedure creates a job.

The procedure is overloaded. The different functionality of each form of syntax is presented along with the syntax declaration.

Syntax

Creates a job in a single call without using an existing program or schedule:

DBMS_SCHEDULER.CREATE_JOB (
   job_name             IN VARCHAR2,
   job_type             IN VARCHAR2,
   job_action           IN VARCHAR2,
   number_of_arguments  IN PLS_INTEGER              DEFAULT 0,
   start_date           IN TIMESTAMP WITH TIME ZONE DEFAULT NULL,
   repeat_interval      IN VARCHAR2                 DEFAULT NULL,
   end_date             IN TIMESTAMP WITH TIME ZONE DEFAULT NULL,
   job_class            IN VARCHAR2                 DEFAULT 'DEFAULT_JOB_CLASS',
   enabled              IN BOOLEAN                  DEFAULT FALSE,
   auto_drop            IN BOOLEAN                  DEFAULT TRUE,
   comments             IN VARCHAR2                 DEFAULT NULL);

Creates a job using a named schedule object and a named program object:

DBMS_SCHEDULER.CREATE_JOB (
   job_name                IN VARCHAR2,
   program_name            IN VARCHAR2,
   schedule_name           IN VARCHAR2,
   job_class               IN VARCHAR2              DEFAULT 'DEFAULT_JOB_CLASS',
   enabled                 IN BOOLEAN               DEFAULT FALSE,
   auto_drop               IN BOOLEAN               DEFAULT TRUE,
   comments                IN VARCHAR2              DEFAULT NULL);

Creates a job using a named program object and an inlined schedule:

DBMS_SCHEDULER.CREATE_JOB (
   job_name             IN VARCHAR2,
   program_name         IN VARCHAR2,
   start_date           IN TIMESTAMP WITH TIME ZONE DEFAULT NULL,
   repeat_interval      IN VARCHAR2                 DEFAULT NULL,
   end_date             IN TIMESTAMP WITH TIME ZONE DEFAULT NULL,
   job_class            IN VARCHAR2                 DEFAULT 'DEFAULT_JOB_CLASS',
   enabled              IN BOOLEAN                  DEFAULT FALSE,
   auto_drop            IN BOOLEAN                  DEFAULT TRUE,
   comments             IN VARCHAR2                 DEFAULT NULL);

Creates a job using a named schedule object and an inlined program:

DBMS_SCHEDULER.CREATE_JOB (
   job_name                IN VARCHAR2,
   schedule_name           IN VARCHAR2,
   job_type                IN VARCHAR2,
   job_action              IN VARCHAR2,
   number_of_arguments     IN PLS_INTEGER       DEFAULT 0,
   job_class               IN VARCHAR2          DEFAULT 'DEFAULT_JOB_CLASS',
   enabled                 IN BOOLEAN           DEFAULT FALSE,
   auto_drop               IN BOOLEAN           DEFAULT TRUE,
   comments                IN VARCHAR2          DEFAULT NULL);

Creates a job using an inlined program and an event:

DBMS_SCHEDULER.CREATE_JOB (
   job_name                IN VARCHAR2,
   job_type                IN VARCHAR2,
   job_action              IN VARCHAR2,
   number_of_arguments     IN PLS_INTEGER       DEFAULT 0,
   start_date              IN TIMESTAMP WITH TIME ZONE,
   event_condition         IN VARCHAR2,
   event_queue             IN VARCHAR2,
   end_date                IN TIMESTAMP WITH TIME ZONE,
   job_class               IN VARCHAR2          DEFAULT 'DEFAULT_JOB_CLASS',
   enabled                 IN BOOLEAN           DEFAULT FALSE,
   auto_drop               IN BOOLEAN           DEFAULT TRUE,
   comments                IN VARCHAR2          DEFAULT NULL);

Creates a job using a named program object and an event:

DBMS_SCHEDULER.CREATE_JOB (
   job_name                IN VARCHAR2,
   program_name            IN VARCHAR2,
   start_date              IN TIMESTAMP WITH TIME ZONE,
   event_condition         IN VARCHAR2,
   queue_spec              IN VARCHAR2,
   end_date                IN TIMESTAMP WITH TIME ZONE,
   job_class               IN VARCHAR2          DEFAULT 'DEFAULT_JOB_CLASS',
   enabled                 IN BOOLEAN           DEFAULT FALSE,
   auto_drop               IN BOOLEAN           DEFAULT TRUE,
   comments                IN VARCHAR2          DEFAULT NULL);

Parameters

Table 93-11 CREATE_JOB Procedure Parameters

Parameter	Description
`job_name`	This attribute specifies the name of the job and uniquely identifies the job. The name has to be unique in the SQL namespace. For example, a job cannot have the same name as a table in a schema. If the job being created will reside in another schema, it must be qualified with the schema name. If `job_name` is not specified, an error is generated. If you want to have a name generated by the Scheduler, you can use the `GENERATE_JOB_NAME` procedure to generate a name and then use the output in the `CREATE_JOB` procedure. The `GENERATE_JOB_NAME` procedure call generates a number from a sequence, which is the job name. You can prefix the number with a string. The job name will then be the string with the number from the sequence appended to it. See "GENERATE_JOB_NAME Function" for more information.
`job_type`	This attribute specifies the type of job that you are creating. If it is not specified, an error is generated. The supported values are: `'PLSQL_BLOCK`' This specifies that the job is an anonymous PL/SQL block. Job or program arguments are not supported when the job or program type is `PLSQL_BLOCK`. In this case, the number of arguments must be 0. `'STORED_PROCEDURE'` This specifies that the job is a PL/SQL or Java stored procedure, or an external C subprogram. Only procedures, not functions with return values, are supported. `'EXECUTABLE'` This specifies that the job is a job external to the database. External jobs are anything that can be executed from the operating system's command line. `Anydata` arguments are not supported with a job or program type of `EXECUTABLE`. The job owner must have the `CREATE` `EXTERNAL` `JOB` system privilege before the job can be enabled or run. '`CHAIN`' This specifies that the job is a chain. Arguments are not supported for a chain, so `number_of_arguments` must be 0.
`job_action`	This attribute specifies the action of the job. The following actions are possible: For a PL/SQL block, the action is to execute PL/SQL code. These blocks must end with a semi-colon. For example, `my_proc();` or `BEGIN my_proc(); END;` or `DECLARE arg pls_integer := 10; BEGIN my_proc2(arg); END;`. Note that the Scheduler wraps `job_action` in its own block and passes the following to PL/SQL for execution: `DECLARE ... BEGIN job_action END;` This is done to declare some internal Scheduler variables. You can include any Scheduler metadata attribute except `event_message` in your PL/SQL code. You use the attribute name as you use any other PL/SQL identifier, and the Scheduler assigns it a value. See Table 93-22 for details on available metadata attributes. For a stored procedure, the action is the name of the stored procedure. You have to specify the schema if the procedure resides in another schema than the job. PL/SQL procedures with `INOUT` or `OUT` arguments are not supported as `job_action` when the job or program type is `STORED_PROCEDURE`. For an executable, the action is the name of the external executable, including the full path name and any command-line arguments. For a chain, the action is the name of a Scheduler chain object. You have to specify the schema of the chain if it resides in a different schema than the job. If `job_action` is not specified for an inline program, an error is generated when creating the job.
`number_of_arguments`	This attribute specifies the number of arguments that the job expects. The range is 0-255, with the default being 0.
`program_name`	The name of the program associated with this job. If the program is of type `EXECUTABLE`, the job owner must have the `CREATE` `EXTERNAL` `JOB` system privilege before the job can be enabled or run.
`start_date`	This attribute specifies the first date on which this job is scheduled to start. If `start_date` and `repeat_interval` are left null, then the job is scheduled to run as soon as the job is enabled. For repeating jobs that use a calendaring expression to specify the repeat interval, `start_date` is used as a reference date. The first time the job will be scheduled to run is the first match of the calendaring expression that is on or after the current date. The Scheduler cannot guarantee that a job will execute on an exact time because the system may be overloaded and thus resources unavailable.
`event_condition`	This is a conditional expression based on the columns of the event source queue table. The expression must have the syntax of an Advanced Queuing rule. Accordingly, you can include user data properties in the expression provided that the message payload is an object type, and that you prefix object attributes in the expression with `tab.user_data`. For more information on rules, see the `DBMS_AQADM`.`ADD_SUBSCRIBER` procedure.
`queue_spec`	This argument specifies the queue into which events that start this particular job will be enqueued (the source queue). If the source queue is a secure queue, the `queue_spec` argument is a string containing a pair of values of the form queue_name, agent name. For non-secure queues, only the queue name need be provided. If a fully qualified queue name is not provided, the queue is assumed to be in the job owner's schema. In the case of secure queues, the agent name provided should belong to a valid agent that is currently subscribed to the queue.
`repeat_interval`	This attribute specifies how often the job should repeat. You can specify the repeat interval by using calendaring or PL/SQL expressions. The expression specified is evaluated to determine the next time the job should run. If `repeat_interval` is not specified, the job will run only once at the specified start date. See "Calendaring Syntax" for further information.
`schedule_name`	The name of the schedule, window, or window group associated with this job.
`end_date`	This attribute specifies the date after which the job will expire and will no longer be executed. When `end_date` is reached, the job is disabled. The `STATE` of the job will be set to `COMPLETED`, and the `enabled` flag will be set to `FALSE`. If no value for `end_date` is specified, the job will repeat forever unless `max_runs` or `max_failures` is set, in which case the job stops when either value is reached. The value for `end_date` must be after the value for `start_date`. If it is not, an error is generated when the job is enabled.
job_priority	This attribute designates the priority of a job relative to other jobs in the same job class only. If two jobs in the same class are scheduled to start at the same time, the one with the higher priority takes precedence. Acceptable values are 1 through 5, where 1 is the highest priority. Default value is 3.
`comments`	This attribute specifies a comment about the job. By default, this attribute is `NULL`.
`enabled`	This attribute specifies whether the job is created enabled or not. The possible settings are `TRUE` or `FALSE`. By default, this attribute is set to `FALSE` and, therefore, the job is created as disabled. A disabled job means that the metadata about the job has been captured and the job exists as a database object but the Scheduler will ignore it and the job coordinator will not pick the job for processing. In order for the job coordinator to process the job, the job has to be enabled. You can enable a job by setting this argument to `TRUE` or by using the `ENABLE` procedure.
`auto_drop`	This flag, if `TRUE`, causes a job to be automatically dropped after it has completed or has been disabled. A job is considered completed if: Its end date (or its schedule's end date) has passed It has run `max_runs` number of times. `max_runs` must be set with `SET_ATTRIBUTE`. It is not a repeating job and has run once A job is disabled when it has failed `max_failures` times. `max_failures` is also set with `SET_ATTRIBUTE`. If this flag is set to `FALSE`, the jobs are not dropped and their metadata is kept until the job is explicitly dropped with the `DROP_JOB` procedure. By default, jobs are created with `auto_drop` set to `TRUE`.

Usage Notes

Jobs are created disabled by default. You must explicitly enable them so that they will become active and scheduled. Before enabling a job, ensure that all program arguments, if any, are defined, either by defining default values in the program object or by supplying values with the job.

To create a job in your own schema, you need to have the CREATE JOB privilege. A user with the CREATE ANY JOB privilege can create a job in any schema. If the job being created will reside in another schema, the job name must be qualified with the schema name. For a job of type EXECUTABLE (or for a job that points to a program of type EXECUTABLE), the job owner must have the CREATE EXTERNAL JOB system privilege before the job can be enabled or run.

Associating a job with a particular class or program requires EXECUTE privileges for that class or program.

Not all possible job attributes can be set with CREATE_JOB. Some must be set after the job is created. For example, job arguments must be set with the SET_JOB_ARGUMENT_VALUE Procedures or the SET_JOB_ANYDATA_VALUE Procedures. Other job attributes, such as job_priority and max_runs, are set with the SET_ATTRIBUTE Procedure.

Note:

The Scheduler runs event-based jobs for each occurrence of an event that matches the job's event condition. However, events that occur while the job is already running are ignored; the event gets consumed, but does not trigger another run of the job.

CREATE_JOB_CLASS Procedure

This procedure creates a job class. Job classes are created in the SYS schema.

Syntax

DBMS_SCHEDULER.CREATE_JOB_CLASS (
   job_class_name            IN VARCHAR2,
   resource_consumer_group   IN VARCHAR2 DEFAULT NULL,
   service                   IN VARCHAR2 DEFAULT NULL,
   logging_level             IN PLS_INTEGER
                                DEFAULT DBMS_SCHEDULER.LOGGING_RUNS,
   log_history               IN PLS_INTEGER DEFAULT NULL,
   comments                  IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-12 CREATE_JOB_CLASS Procedure Parameters

Parameter	Description
`job_class_name`	The name of the class being created. A schema other than `SYS` cannot be specified. This attribute specifies the name of the job class and uniquely identifies the job class. The name has to be unique in the SQL namespace. For example, a job class cannot have the same name as a table in a schema.
`resource_consumer_group`	This attribute specifies the resource consumer group this class is associated with. A resource consumer group is a set of synchronous or asynchronous sessions that are grouped together based on their processing needs. A job class has a many-to-one relationship with a resource consumer group. The resource consumer group that the job class associates with will determine the resources that will be allocated to the job class. If the resource consumer group that a job class is associated with is dropped, the job class will then be associated with the default resource consumer group. If no resource consumer group is specified, the job class is associated with the default resource consumer group. If the specified resource consumer group does not exist when creating the job class, an error occurs. If `resource_consumer_group` is specified, you cannot specify a service (it must be `NULL`). Also, if a service is specified, `resource_consumer_group` must be `NULL`.
`service`	This attribute specifies the database service that the jobs in this class will have affinity to. In a RAC environment, this means that the jobs in this class will only run on those database instances that are assigned to the specific service. If a service is specified, `resource_consumer_group` must be `NULL`. Note that a service can be mapped to a resource consumer group, so you can also control resources allocated to jobs by specifying a service. See `DBMS_RESOURCE_MANAGER`.`SET_CONSUMER_GROUP_MAPPING` for details. If no service is specified, the job class will belong to the default service, which means it will have no service affinity and any one of the database instances within the cluster might run the job. If the service that a job class belongs to is dropped, the job class will then belong to the default service. If the specified service does not exist when creating the job class, then an error occurs.
`logging_level`	This attribute specifies how much information is logged. The three possible options are: `DBMS_SCHEDULER.LOGGING_OFF` No logging will be performed for any jobs in this class. `DBMS_SCHEDULER.LOGGING_RUNS` The Scheduler will write detailed information to the job log for all runs of each job in this class. This is the default. `DBMS_SCHEDULER.LOGGING_FULL` In addition to recording every run of a job, the Scheduler will record all operations performed on all jobs in this class. In other words, every time a job is created, enabled, disabled, altered, and so on will be recorded in the log.
`log_history`	This enables you to control the amount of logging the Scheduler performs. To prevent the job log and the window log from growing indiscriminately, the Scheduler has an attribute that specifies how much history (in days) to keep. Once a day, the Scheduler will automatically purge all log entries from both the job log as well as the window log that are older than the specified history. The default is 30 days. You can change the default by using the `SET_SCHEDULER_ATTRIBUTE` procedure. For example, to change it to 90 days, issue the following statement: `DBMS_SCHEDULER.SET_SCHEDULER_ATTRIBUTE ('log_history','90');` The range of valid values is 1 through 999.
`comments`	This attribute is for an optional comment about the job class. By default, this attribute is `NULL`.

Usage Notes

For users to create jobs that belong to a job class, the job owner must have EXECUTE privileges on the job class. Therefore, after the job class has been created, EXECUTE privileges must be granted on the job class so that users create jobs belonging to that class. You can also grant the EXECUTE privilege to a role.

Creating a job class requires the MANAGE SCHEDULER system privilege.

CREATE_PROGRAM Procedure

This procedure creates a program.

Syntax

DBMS_SCHEDULER.CREATE_PROGRAM (
   program_name             IN VARCHAR2,
   program_type             IN VARCHAR2,
   program_action           IN VARCHAR2,
   number_of_arguments      IN PLS_INTEGER DEFAULT 0,
   enabled                  IN BOOLEAN DEFAULT FALSE,
   comments                 IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-13 CREATE_PROGRAM Procedure Parameters

Parameter	Description
`program_name`	This attribute specifies a unique identifier for the program. The name has to be unique in the SQL namespace. For example, a program cannot have the same name as a table in a schema. If no name is specified, then an error occurs.
`program_type`	This attribute specifies the type of program you are creating. If it is not specified then you will get an error. There are three supported values for `program_type`: `'PLSQL_BLOCK'` This specifies that the program is a PL/SQL block. Job or program arguments are not supported when the job or program type is PLSQL_BLOCK. In this case, the number of arguments must be 0. `'STORED_PROCEDURE'` This specifies that the program is a PL/SQL or Java stored procedure, or an external C subprogram. Only procedures, not functions with return values, are supported. PL/SQL procedures with `INOUT` or `OUT` arguments are not supported. `'EXECUTABLE'` This specifies that the program is external to the database. External programs implies anything that can be executed from the operating system's command line. `AnyData` arguments are not supported with job or program type EXECUTABLE.
`program_action`	This attribute specifies the action of the program. The following actions are possible: For a PL/SQL block, the action is to execute PL/SQL code. These blocks must end with a semi-colon. For example, `my_proc();` or `BEGIN my_proc(); END;` or `DECLARE arg pls_integer := 10; BEGIN my_proc2(arg); END;`. Note that the Scheduler wraps `job_action` in its own block and passes the following to PL/SQL for execution: `DECLARE ... BEGIN job_action END;` This is done to declare some internal Scheduler variables. You can include any Scheduler metadata attribute except `event_message` in your PL/SQL code. You use the attribute name as you use any other PL/SQL identifier, and the Scheduler assigns it a value. See Table 93-22 for details on available metadata attributes. For a stored procedure, the action is the name of the stored procedure. You have to specify the schema if the procedure resides in another schema than the job. For an executable, the action is the name of the external executable, including the full path name and any command-line arguments. If `program_action` is not specified, an error is generated If it is an anonymous block, special Scheduler metadata may be accessed using the following variable names: `job_name`, `job_owner`, `job_start`, `window_start`, `window_end`. For more information on these, see the information regarding `define_metadata_argument`.
`number_of_arguments`	This attribute specifies the number of arguments the program takes. If this parameter is not specified then the default will be 0. A program can have a maximum of 255 arguments. If the `program_type` is `PLSQL_BLOCK`, this field is ignored.
`enabled`	This flag specifies whether the program should be created enabled or not. If the flag is set to `TRUE`, then validity checks will be made and the program will be created `ENABLED` should all the checks be successful. By default, this flag is set to `FALSE`, which means that the program is not created enabled. You can also call the `ENABLE` procedure to enable the program before it can be used.
`comments`	A comment about the program. By default, this attribute is `NULL`.

Usage Notes

To create a program in his own schema, a user needs the CREATE JOB privilege. A user with the CREATE ANY JOB privilege can create a program in any schema. A program is created in a disabled state by default (unless the enabled field is set to TRUE). It cannot be executed by a job until it is enabled.

For other users to use your programs, they must have EXECUTE privileges, therefore once a program has been created, you have to grant EXECUTE privileges on it.

CREATE_SCHEDULE Procedure

This procedure creates a schedule.

Syntax

DBMS_SCHEDULER.CREATE_SCHEDULE (
   schedule_name          IN VARCHAR2,
   start_date             IN TIMESTAMP WITH TIMEZONE DEFAULT NULL,
   repeat_interval        IN VARCHAR2,
   end_date               IN TIMESTAMP WITH TIMEZONE DEFAULT NULL,
   comments               IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-14 CREATE_SCHEDULE Procedure Parameters

Parameter	Description
`schedule_name`	This attribute specifies a unique identifier for the schedule. The name has to be unique in the SQL namespace. For example, a schedule cannot have the same name as a table in a schema. If no name is specified, then an error occurs.
`start_date`	This attribute specifies the first date on which this schedule becomes valid. For a repeating schedule, the value for `start_date` is a reference date. In this case, the start of the schedule is not the `start_date`. It depends on the repeat interval specified. `start_date` is used to determine the first instance of the schedule. If `start_date` is specified in the past and no value for `repeat_interval` is specified, the schedule is invalid. For a repeating job or window, `start_date` can be derived from the `repeat_interval`, if it is not specified.
`repeat_interval`	This attribute specifies how often the schedule should repeat. It is expressed using calendaring syntax. See "Calendaring Syntax" for further information. PL/SQL expressions are not allowed as repeat intervals for named schedules.
`end_date`	The date after which jobs will not run and windows will not open. A non-repeating schedule that has no `end_date` will be valid forever. `end_date` has to be after the `start_date`. If this is not the case, then an error will be generated when the schedule is created.
`comments`	This attribute specifies an optional comment about the schedule. By default, this attribute is `NULL`.

Usage Notes

CREATE_WINDOW Procedures

This procedure creates a recurring time window and associates it with a resource plan. The window can then be used to schedule jobs, which run under the associated resource plan.

The procedure is overloaded.

Syntax

Creates a window using a named schedule object:

DBMS_SCHEDULER.CREATE_WINDOW (
   window_name             IN VARCHAR2,
   resource_plan           IN VARCHAR2,
   schedule_name           IN VARCHAR2,
   duration                IN INTERVAL DAY TO SECOND,
   window_priority         IN VARCHAR2                 DEFAULT 'LOW',
   comments                IN VARCHAR2                 DEFAULT NULL);

Creates a window using an inlined schedule:

DBMS_SCHEDULER.CREATE_WINDOW (
   window_name             IN VARCHAR2,
   resource_plan           IN VARCHAR2,
   start_date              IN TIMESTAMP WITH TIME ZONE DEFAULT NULL,
   repeat_interval         IN VARCHAR2,
   end_date                IN TIMESTAMP WITH TIME ZONE DEFAULT NULL,
   duration                IN INTERVAL DAY TO SECOND,
   window_priority         IN VARCHAR2                 DEFAULT 'LOW',
   comments                IN VARCHAR2                 DEFAULT NULL);

Parameters

Table 93-15 CREATE_WINDOW Procedure Parameters

Parameter	Description
`window_name`	This attribute uniquely identifies the window. The name has to be unique in the SQL namespace. All windows are in the `SYS` schema, so you can optionally preface the window name with '`SYS.`'
`resource_plan`	This attribute specifies the resource plan that is automatically activated when the window opens. When the window closes, the system switches to the appropriate resource plan, which in most cases is the resource plan that was in effect before the window opened, but can also be the resource plan of yet another window. Only one resource plan can be associated with a window. It may be `NULL` or the empty string (""). When it is `NULL`, the resource plan that is in effect when the window opens stays in effect for the duration of the window. When it is the empty string, the resource manager is disabled for the duration of the window. If the window is open and the resource plan is dropped, then the resource allocation for the duration of the window is not affected.
`start_date`	This attribute specifies the first date on which this window is scheduled to open. If the value for `start_date` specified is in the past or is not specified, the window opens as soon as it is created. For repeating windows that use a calendaring expression to specify the repeat interval, the value for `start_date` is a reference date. The first time the window opens depends on the repeat interval specified and the value for `start_date`.
`duration`	This attribute specifies how long the window will be open for. For example, `'interval '5' hour'` for five hours. There is no default value for this attribute. Therefore, if none is specified when creating the window, an error occurs. The duration is of type interval day to seconds and ranges from one minute to 99 days.
`schedule_name`	The name of the schedule associated with the window.
`repeat_interval`	This attribute specifies how often the window should repeat. It is expressed using the Scheduler's calendaring syntax. See "Calendaring Syntax" for more information. A PL/SQL expression cannot be used to specify the repeat interval for a window. The expression specified is evaluated to determine the next time the window should open. If no repeat_interval is specified, the window will open only once at the specified start date.
`end_date`	This attribute specifies the date after which the window will no longer open. When the value for `end_date` is reached, the window is disabled. In the `*_SCHEDULER_WINDOWS` views, the enabled flag of the window will be set to `FALSE`. A non-repeating window that has no value for end_date opens only once for the duration of the window. For a repeating window, if no `end_date` is specified then the window will keep repeating forever. The `end_date` has to be after the start_date. If this is not the case, then an error is generated when the window is created.
`window_priority`	This attribute is only relevant when two windows overlap. Because only one window can be in effect at one time, the window priority will be used to determine which window will be opened. The two possible values for this attribute are '`HIGH`' and '`LOW`'. A high priority window has precedence over a low priority window, which implies that the low priority window does not open if it overlaps with a high priority window. By default, a window is created with a priority of '`LOW`'.
`comments`	This attribute specifies an optional comment about the window. By default, this attribute is `NULL`.

Usage Notes

Creating a window requires the MANAGE SCHEDULER privilege. Windows always reside in the SYS schema.

Scheduler windows are the principal mechanism used to automatically switch resource plans according to a schedule. You can also manually activate a resource plan by using the ALTER SYSTEM SET RESOURCE_MANAGER_PLAN statement or the DBMS_RESOURCE_MANAGER.SWITCH_PLAN package procedure. Note that either of these manual methods can also disable resource plan switching by Scheduler windows. For more information, see Oracle Database Administrator's Guide and "SWITCH_PLAN Procedure".

CREATE_WINDOW_GROUP Procedure

This procedure creates a new window group.

Syntax

DBMS_SCHEDULER.CREATE_WINDOW_GROUP (
   group_name            IN VARCHAR2,
   window_list           IN VARCHAR2 DEFAULT NULL,
   comments              IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-16 CREATE_WINDOW_GROUP Procedure Parameters

Parameter Description

group_name

The name of the window group

window_list

A list of the windows assigned to the window group. If a window that does not exist is specified, an error is generated and the window group is not created.

Windows can also be added using the ADD_WINDOW_GROUP_MEMBER procedure. A window group cannot be a member of another window group.

Can be NULL.

comments

A comment about the window group

Usage Notes

Creating a window group requires the MANAGE SCHEDULER privilege. Window groups reside in the SYS schema. Window groups, like windows, are created with access to PUBLIC, therefore, no privileges are required to access window groups.

A window group cannot contain another window group.

DEFINE_ANYDATA_ARGUMENT Procedure

This procedure defines a name or default value for a program argument that is of a complex type and must be encapsulated within an ANYDATA object. A job that references the program can override the default value.

Syntax

DBMS_SCHEDULER.DEFINE_ANYDATA_ARGUMENT (
   program_name            IN VARCHAR2,
   argument_position       IN PLS_INTEGER,
   argument_name           IN VARCHAR2 DEFAULT NULL,
   argument_type           IN VARCHAR2,
   default_value           IN SYS.ANYDATA,
   out_argument            IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-17 DEFINE_ANYDATA_ARGUMENT Procedure Parameters

Parameter	Description
`program_name`	The name of the program to be altered. A program with this name must exist.
`argument_position`	The position of the argument as it is passed to the executable. Argument numbers go from one to the `number_of_arguments` specified for the program. This must be unique, so it will replace any argument already defined at this position.
`argument_name`	The name to assign to the argument. It is optional, but must be unique for the program if it is specified. If you assign a name, the name can then be used by other package procedures, including the SET_JOB_ANYDATA_VALUE Procedures.
`argument_type`	The data type of the argument being defined. This is not verified or used by the Scheduler. It is only used by the user of the program when deciding what value to assign to the argument.
`default_value`	The default value to be assigned to the argument encapsulated within an `AnyData` object. This is optional.
`out_argument`	This parameter is reserved for future use. It must be set to `FALSE`.

Usage Notes

All program arguments from 1 to the number_of_arguments value must be defined before a program can be enabled. If a default value for an argument is not defined with this procedure, a value must be defined in the job.

Defining a program argument requires that you be the owner of the program or have ALTER privileges on that program. You can also define a program argument if you have the CREATE ANY JOB privilege.

See Also:

"DEFINE_PROGRAM_ARGUMENT Procedures"
"SET_JOB_ANYDATA_VALUE Procedures"

DEFINE_CHAIN_EVENT_STEP Procedure

This procedure adds or replaces a chain step and associates it with an event schedule or an inline event. Once started in a running chain, this step will not complete until the specified event has occurred. Every step in a chain must be defined before the chain can be enabled and used. Defining a step gives it a name and specifies what happens during the step. If a step already exists with this name, the new step will replace the old one.

Syntax

DBMS_SCHEDULER.DEFINE_CHAIN_EVENT_STEP (
   chain_name              IN VARCHAR2,
   step_name               IN VARCHAR2,
   event_schedule_name     IN VARCHAR2,
   timeout                 IN INTERVAL DAY TO SECOND DEFAULT NULL);

DBMS_SCHEDULER.DEFINE_CHAIN_EVENT_STEP (
   chain_name              IN VARCHAR2,
   step_name               IN VARCHAR2,
   event_condition         IN VARCHAR2,
   queue_spec              IN VARCHAR2,
   timeout                 IN INTERVAL DAY TO SECOND DEFAULT NULL);

Parameters

Table 93-18 DEFINE_CHAIN_EVENT_STEP Procedure Parameters

Parameter	Description
`chain_name`	The name of the chain that the step is in
`step_name`	The name of the step
`event_schedule_name`	The name of the event schedule that the step waits for
`timeout`	This parameter is reserved for future use
`event_condition`	See the CREATE_EVENT_SCHEDULE Procedure
`queue_spec`	See the CREATE_EVENT_SCHEDULE Procedure

Usage Notes

Defining a chain step requires ALTER privileges on the chain either by being the owner of the chain, or by having the ALTER object privilege on the chain or by having the CREATE ANY JOB system privilege.

See Also:

"DEFINE_CHAIN_STEP Procedure"

DEFINE_CHAIN_RULE Procedure

This procedure adds a new rule to an existing chain, specified as a condition-action pair. The condition is expressed using either SQL or the Scheduler chain condition syntax, and indicates the prerequisites for the action to occur. The action specifies what is to be done as a result of the condition being met.

An actual rule object is created to store the rule in the schema in which the chain resides. If a rule name is given, this name will be used for the rule object. If a rule name is given and a rule already exists with this name in the chain's schema, the existing rule will be altered. (A schema different than the chain's schema cannot be specified). If no rule name is given, one will be generated of the form SCHED_RULE${N}.

Syntax

DBMS_SCHEDULER.DEFINE_CHAIN_RULE (
   chain_name              IN VARCHAR2,
   condition               IN VARCHAR2,
   action                  IN VARCHAR2,
   rule_name               IN VARCHAR2 DEFAULT NULL,
   comments                IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-19 DEFINE_CHAIN_RULE Procedure Parameters

Parameter	Description
`chain_name`	The name of the chain to alter
`condition`	A boolean expression expressed using either SQL or the Scheduler chain condition syntax. (Scheduler chain condition syntax is described below.) The expression must evaluate to `TRUE` for the action to be performed. If the condition is expressed with SQL, it must use the syntax of a `SELECT` statement `WHERE` clause. You can refer to chain step attributes by using the chain step name as a bind variable. The bind variable syntax is `:step_name.attribute`. (`step_name` refers to a typed object.) Possible attributes are: `completed`, `state`, `start_date`, `end_date`, `error_code`, and `duration`. Possible values for the `state` attribute include: `'NOT_STARTED', 'SCHEDULED', 'RUNNING', 'PAUSED', 'STALLED', 'SUCCEEDED', 'FAILED'`, and `'STOPPED'`. If a step is in the state `'SUCCEEDED'`, `'FAILED'`, or `'STOPPED'`, its `completed` attribute is set to `'TRUE'`, otherwise `completed` is `'FALSE'`. Every chain must have a rule that evaluates to `TRUE` to start the chain. For this purpose, you can use a rule that has '`TRUE`' as its condition if you are using Schedule chain condition syntax, or '`1=1`' as its condition if you are using SQL syntax.
`action`	The action to be performed when the rule evaluates to `TRUE`. The action must consist of at least a keyword with an optional value and an optional delay clause. Possible actions include: [`AFTER` `delay_interval`] `START` `step_1`[,`step_2` ...] `STOP` `step_1`[,`step_2` ...] `END` [{`end_value`\|`step_name.error_code`}] At the beginning of the `START` action, a delay clause can be given which specifies a delay interval to wait before performing the action. `delay_interval` is a formatted datetime interval of the form `HH:MM:SS`.
`rule_name`	The name of the rule that will be created. If no rule_name is given, one will be generated of the form `SCHED_RULE$_{N}`.
`comments`	An optional comment describing the rule. This will be stored in the rule object created.

Chain Condition Syntax

The Scheduler chain condition syntax provides an easy way to construct a condition using the states and error codes of steps in the current chain. The following are the available constructs, all of which are boolean expressions:

TRUE
FALSE
stepname [NOT] SUCCEEDED 
stepname [NOT] FAILED 
stepname [NOT] STOPPED 
stepname [NOT] COMPLETED 
stepname ERROR_CODE IN (integer, integer, integer ...)
stepname ERROR_CODE NOT IN (integer, integer, integer ...)
stepname ERROR_CODE = integer
stepname ERROR_CODE != integer
stepname ERROR_CODE <> integer
stepname ERROR_CODE > integer
stepname ERROR_CODE >= integer
stepname ERROR_CODE < integer
stepname ERROR_CODE <= integer

The following boolean operators are available to create more complex conditions:

expression AND expression
expression OR expression
NOT (expression)

integer can be positive or negative. Parentheses may be used for clarity or to enforce ordering. You must use parentheses with the NOT operator.

Usage Notes

Defining a chain rule requires ALTER privileges on the chain (either by being the owner, or by having ALTER privileges on the chain or by having the CREATE ANY JOB system privilege).

You must define at least one rule that starts the chain and at least one that ends it. See the section "Adding Rules to a Chain" in Oracle Database Administrator's Guide for more information.

Examples

The following are examples of using rule conditions and rule actions.

Rule Conditions Using Scheduler Chain Condition Syntax

'step1 completed'
-- satisfied when step step1 has completed. (step1 completed is also TRUE when any 
-- of the following are TRUE: step1 succeeded, step1 failed, step1 stopped.)

'step1 succeeded and step2 succeeded'
-- satisfied when steps step1 and step2 have both succeeded

'step1 error_code > 100'
-- satisfied when step step1 has failed with an error_code greater than 100

'step1 error_code IN (1, 3, 5, 7)'
-- satisfied when step step1 has failed with an error_code of 1, 3, 5, or 7

Rule Conditions Using SQL Syntax

':step1.completed = ''TRUE'' AND :step1.end_date >SYSDATE-1/24'
--satisfied when step step1 completed less than an hour ago

':step1.duration > interval ''5'' minute'
-- satisfied when step step1 has completed and took longer than 5 minutes to complete

Rule Actions

'AFTER 01:00:00 START step1, step2'
--After an hour start steps step1 and step2

'STOP step1'
--Stop step step1

END step4.error_code'
--End the chain with the error code that step step4 finished with. If step4 has not completed, the chain will be ended unsuccessfully with error code 27435.

'END' or 'END 0'
--End the chain successfully (with error_code 0)

'END 100'
--End the chain unsuccessfully with error code 100.

DEFINE_CHAIN_STEP Procedure

This procedure adds or replaces a chain step and associates it with a program or a nested chain. When the chain step is started, the specified program or chain is run. If a step already exists with the name supplied in the chain_name argument, the new step replaces the old one.

The chain owner must have EXECUTE privileges on the program or chain associated with the step. Only one program or chain can run during a step.

Syntax

DBMS_SCHEDULER.DEFINE_CHAIN_STEP (
   chain_name              IN VARCHAR2,
   step_name               IN VARCHAR2,
   program_name            IN VARCHAR2);

Parameters

Table 93-20 DEFINE_CHAIN_STEP Procedure Parameters

Parameter	Description
`chain_name`	The name of the chain to alter.
`step_name`	The name of the step being defined. If a step already exists with this name, the new step will replace the old one.
`program_name`	The name of a program or chain to run during this step. The chain owner must have `EXECUTE` privileges on this program or chain.

Usage Notes

Defining a chain step requires ALTER privileges on the chain (either by being the owner, or by having ALTER privileges on the chain or by having the CREATE ANY JOB system privilege).

See Also:

"DEFINE_CHAIN_EVENT_STEP Procedure"

DEFINE_METADATA_ARGUMENT Procedure

This procedure defines a special metadata argument for the program. The Scheduler can pass Scheduler metadata through this argument to your stored procedure or other executable. You cannot set values for jobs using this argument.

Syntax

DBMS_SCHEDULER.DEFINE_METADATA_ARGUMENT (
  program_name            IN VARCHAR2,
  metadata_attribute      IN VARCHAR2,
  argument_position       IN PLS_INTEGER,
  argument_name           IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-21 DEFINE_METADATA_ARGUMENT Procedure Parameters

Parameter	Description
`program_name`	The name of the program to be altered
`metadata_attribute`	The metadata to be passed. Valid metadata attributes are: '`job_name`', '`job_subname`', '`job_owner`', '`job_start`', '`window_start`', '`window_end`', and '`event_message`'. Table Table 93-22 describes these attributes in detail.
`argument_position`	The position of the argument as it is passed to the executable. This cannot be greater than the `number_of_arguments` specified for the program. This must be unique, so it will replace any argument already defined at this position.
`argument_name`	The name to assign to the argument. It is optional, but must be unique for the program if it is specified. If you assign a name, the name can then be used by other package procedures.

Table 93-22 Metadata Attributes

Metadata Attribute	Data Type	Description
`job_name`	`VARCHAR2`	Name of the currently running job
`job_subname`	`VARCHAR2`	Subname of the currently running job. The name + subname form a unique identifier for a job that is running a chain step. `NULL` if the job is not part of a chain.
`job_owner`	`VARCHAR2`	Owner of the currently running job
`job_start`	`TIMESTAMP WITH TIME ZONE`	When the currently running job started
`window_start`	`TIMESTAMP WITH TIME ZONE`	If the job was started by a window, the time that the window opened
`window_end`	`TIMESTAMP WITH TIME ZONE`	If the job was started by a window, the time that the window is scheduled to close
`event_message`	(See Description)	For an event-based job, the message content of the event that started the job. The data type of this attribute depends on the queue used for the event. It has the same type as the `USER_DATA` column of the queue table.

Usage Notes

All metadata attributes except event_message can also be used in PL/SQL blocks that you enter into the job_action or program_action attributes of jobs or programs, respectively. You use the attribute name as you use any other PL/SQL identifier, and the Scheduler assigns it a value.

DEFINE_PROGRAM_ARGUMENT Procedures

This procedure defines a name or default value for a program argument. If no default value is defined for a program argument, the job that references the program must supply an argument value. (The job can also override a default value.)

This procedure is overloaded.

Syntax

Defines a program argument without a default value:

PROCEDURE define_program_argument(
   program_name            IN VARCHAR2,
   argument_position       IN PLS_INTEGER,
   argument_name           IN VARCHAR2 DEFAULT NULL,
   argument_type           IN VARCHAR2,
   out_argument            IN BOOLEAN DEFAULT FALSE);

Defines a program argument with a default value:

PROCEDURE define_program_argument(
   program_name            IN VARCHAR2,
   argument_position       IN PLS_INTEGER,
   argument_name           IN VARCHAR2 DEFAULT NULL,
   argument_type           IN VARCHAR2,
   default_value           IN VARCHAR2,
   out_argument            IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-23 DEFINE_PROGRAM_ARGUMENT Procedure Parameters

Parameter	Description
`program_name`	The name of the program to be altered. A program with this name must exist.
`argument_position`	The position of the argument as it is passed to the executable. Argument numbers go from one to the `number_of_arguments` specified for the program. This must be unique so it will replace any argument already defined at this position.
`argument_name`	The name to assign to the argument. It is optional, but must be unique for the program if it is specified. If you assign a name, the name can then be used by other package procedures, including the SET_JOB_ARGUMENT_VALUE Procedures.
`argument_type`	The data type of the argument being defined. This is not verified or used by the Scheduler. It is only used by the user of the program when deciding what value to assign to the argument.
`default_value`	The default value to be assigned to the argument if none is specified by the job.
`out_argument`	This parameter is reserved for future use. It must be set to `FALSE`.

Usage Notes

See Also:

"DEFINE_ANYDATA_ARGUMENT Procedure"
"SET_JOB_ARGUMENT_VALUE Procedures"

DISABLE Procedure

This procedure disables a program, job, chain, window, or window group.

Syntax

DBMS_SCHEDULER.DISABLE (
   name              IN VARCHAR2,
   force             IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-24 DISABLE Procedure Parameters

Parameter Description

Parameter	Description
`name`	The name of the object being disabled. Can be a comma-delimited list. If a job class name is specified, then all the jobs in the job class are disabled. The job class is not disabled. If a window group name is specified, then the window group will be disabled, but the windows that are members of the window group will not be disabled.
`force`	Whether to ignore dependencies. See the usage notes for more information.

name

The name of the object being disabled. Can be a comma-delimited list.

If a job class name is specified, then all the jobs in the job class are disabled. The job class is not disabled.

If a window group name is specified, then the window group will be disabled, but the windows that are members of the window group will not be disabled.

force

Whether to ignore dependencies. See the usage notes for more information.

Usage Notes

Disabling an object that is already disabled does not generate an error. Because the DISABLE procedure is used for several Scheduler objects, when disabling windows and window groups, they must be preceded by SYS.

The purpose of the force option is to point out dependencies. No dependent objects are altered.

To run DISABLE for a window or window group, you must have the MANAGE SCHEDULER privilege. Otherwise, you must be the owner of the object being disabled or have ALTER privileges on that object or have the CREATE ANY JOB privilege.

Jobs

Disabling a job means that, although the metadata of the job is there, it should not run and the job coordinator will not pick up these jobs for processing. When a job is disabled, its state in the job queue is changed to disabled.

If force is set to FALSE and the job is currently running, an error is returned.

If force is set to TRUE, the job is disabled, but the currently running instance is allowed to finish.

Programs

When a program is disabled, the status is changed to disabled. A disabled program implies that, although the metadata is still there, jobs that point to this program cannot run.

If force is set to FALSE, the program must be unreferenced by any job otherwise an error will occur.

If force is set to TRUE, those jobs that point to the program will not be disabled, however, they will fail at runtime because their program will not be valid.

Running jobs that point to the program are not affected by the DISABLE call, and are allowed to continue

Any argument that pertains to the program will not be affected when the program is disabled.

Windows

This means that the window will not open, however, the metadata of the window is still there, so it can be reenabled.

If force is set to FALSE, the window must not be open or referenced by any job otherwise an error will occur.

If force is set to TRUE, disabling a window that is open will succeed but the window will not be closed. It will prevent the window from opening in the future until it is re-enabled.

When the window is disabled, those jobs that have the window as their schedule will not be disabled.

Window Groups

When a window group is disabled, jobs, other than a running job, that has the window group as its schedule will not run even if the member windows open. However, if the job had one of the window group members as its schedule, it would still run.

The metadata of the window group is still there, so it can be reenabled. Note that the members of the window group will still open.

If force is set to FALSE, the window group must not have any members that are open or referenced by any job otherwise an error will occur.

If force is set to TRUE:

The window group is disabled and the open window will be not closed or disabled. It will be allowed to continue to its end.
The window group is disabled but those jobs that have the window group as their schedule will not be disabled.

Job Chains

When a chain is disabled, the metadata for the chain is still there, but jobs that point to it will not be able to be run. This allows changes to the chain to be made safely without the risk of having an incompletely specified chain run.If force is set to FALSE, the chain must be unreferenced by any job, otherwise an error will occur.If force is set to TRUE, those jobs that point to the chain will not be disabled, however, they will fail at runtime.Running jobs that point to this chain are not affected by the DISABLE call and are allowed to complete.

DROP_CHAIN Procedure

This procedure drops an existing chain.

Syntax

DBMS_SCHEDULER.DROP_CHAIN (
   chain_name              IN VARCHAR2,
   force                   IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-25 DROP_CHAIN Procedure Parameters

Parameter Description

Parameter	Description
`chain_name`	The name of a chain to drop. Can also be a comma-delimited list of chains.
`force`	If `force` is set to `FALSE`, the chain must be unreferenced by any job otherwise an error will occur. If `force` is set to `TRUE`, all jobs pointing to the chain are disabled before dropping the chain.Running jobs that point to this chain will be stopped before the chain is dropped.

chain_name

The name of a chain to drop. Can also be a comma-delimited list of chains.

force

If force is set to FALSE, the chain must be unreferenced by any job otherwise an error will occur.

If force is set to TRUE, all jobs pointing to the chain are disabled before dropping the chain.Running jobs that point to this chain will be stopped before the chain is dropped.

Usage Notes

Dropping a chain requires alter privileges on the chain (either by being the owner, or by having ALTER privileges on the chain or by having the CREATE ANY JOB system privilege).

All steps associated with the chain are dropped. If no rule set was specified when the chain was created, then the automatically created rule set and evaluation context associated with the chain are also dropped, so the user needs to have the privileges required to do this. See the DBMS_RULE_ADM.DROP_RULE_SET and DBMS_RULE_ADM.DROP_EVALUATION_CONTEXT procedures for more information.

If force is FALSE, no jobs must be using this chain. If force is TRUE, any jobs that use this chain will be disabled before dropping the chain (and any of these jobs that are running will be stopped).

DROP_CHAIN_RULE Procedure

This procedure removes a rule from an existing chain. The rule object corresponding to this rule will also be dropped. The chain will not be disabled. If dropping this rule makes the chain invalid, the user should first disable the chain to ensure that it does not run.

Syntax

DBMS_SCHEDULER.DROP_CHAIN_RULE (
   chain_name              IN VARCHAR2,
   rule_name               IN VARCHAR2,
   force                   IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-26 DROP_CHAIN_RULE Procedure Parameters

Parameter	Description
`chain_name`	The name of the chain to alter
`rule_name`	The name of the rule to drop
`force`	If `force` is set to `TRUE`, the drop operation proceeds even if the chain is currently running. The running chain is not stopped or interrupted. If `force` is set to `FALSE` and the chain is running, an error is generated.

Usage Notes

Dropping a chain rule requires alter privileges on the chain (either by being the owner, or by having ALTER privileges on the chain or by having the CREATE ANY JOB system privilege).

Dropping a chain rule also drops the underlying rule database object so the user needs to have the privileges to drop this rule object. See the DBMS_RULE_ADM.DROP_RULE procedure for more information.

DROP_CHAIN_STEP Procedure

This procedure drops a chain step. If this chain step is still used in the chain rules, the chain will be disabled.

Syntax

DBMS_SCHEDULER.DROP_CHAIN_STEP (
   chain_name              IN VARCHAR2,
   step_name               IN VARCHAR2,
   force                   IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-27 DROP_CHAIN_STEP Procedure Parameters

Parameter	Description
`chain_name`	The name of the chain to alter
`step_name`	The name of the step being dropped. Can be a comma-separated list.
`force`	If `force` is set to `TRUE`, this succeeds even if this chain is currently running. The running chain will not be stopped or interrupted.If `force` is set to `FALSE` and this chain is currently running, an error is thrown.

Usage Notes

Dropping a chain step requires ALTER privileges on the chain (either by being the owner, or by having ALTER privileges on the chain or by having the CREATE ANY JOB system privilege).

DROP_JOB Procedure

This procedure drops a job or all jobs in a job class. It results in the job being removed from the job queue, its metadata being removed, and no longer being visible in the *_SCHEDULER_JOBS views. Therefore, no more runs of the job will be executed. Dropping a job also drops all argument values set for that job.

Syntax

DBMS_SCHEDULER.DROP_JOB (
   job_name                IN VARCHAR2,
   force                   IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-28 DROP_JOB Procedure Parameters

Parameter Description

Parameter	Description
`job_name`	The name of a job or job class. Can be a comma-delimited list. For a job class, the `SYS` schema should be specified. If the name of a job class is specified, the jobs that belong to that job class are dropped, but the job class itself is not dropped.
`force`	If `force` is set to `FALSE`, and an instance of the job is running at the time of the call, the call results in an error. If `force` is set to `TRUE`, the Scheduler first attempts to stop the running job instance (by issuing the `STOP_JOB` call with the force flag set to `false`), and then drops the job.

job_name

The name of a job or job class. Can be a comma-delimited list. For a job class, the SYS schema should be specified.

If the name of a job class is specified, the jobs that belong to that job class are dropped, but the job class itself is not dropped.

force

If force is set to FALSE, and an instance of the job is running at the time of the call, the call results in an error.

If force is set to TRUE, the Scheduler first attempts to stop the running job instance (by issuing the STOP_JOB call with the force flag set to false), and then drops the job.

Usage Notes

Dropping a job requires ALTER privileges on the job either by being the owner of the job, or by having the ALTER object privilege on the job or by having the CREATE ANY JOB system privilege.

DROP_JOB_CLASS Procedure

This procedure drops a job class. Dropping a job class means that all the metadata about the job class is removed from the database.

Syntax

DBMS_SCHEDULER.DROP_JOB_CLASS (
   job_class_name          IN VARCHAR2,
   force                   IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-29 DROP_JOB_CLASS Procedure Parameters

Parameter Description

Parameter	Description
`job_class_name`	The name of the job class. Can be a comma-delimited list.
`force`	If `force` is set to `FALSE`, a class must be unreferenced by any jobs to be dropped otherwise an error will occur. If `force` is set to `TRUE`, jobs belonging to the class are disabled and their class is set to the default class. Only if this is successful will the class be dropped. Running jobs that belong to the job class are not affected.

job_class_name

The name of the job class. Can be a comma-delimited list.

force

If force is set to FALSE, a class must be unreferenced by any jobs to be dropped otherwise an error will occur.

If force is set to TRUE, jobs belonging to the class are disabled and their class is set to the default class. Only if this is successful will the class be dropped.

Running jobs that belong to the job class are not affected.

Usage Notes

Dropping a job class requires the MANAGE SCHEDULER system privilege.

DROP_PROGRAM Procedure

This procedure drops a program. Any arguments that pertain to the program are also dropped when the program is dropped.

Syntax

DBMS_SCHEDULER.DROP_PROGRAM (
   program_name            IN VARCHAR2,
   force                   IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-30 DROP_PROGRAM Procedure Parameters

Parameter Description

Parameter	Description
`program_name`	The name of the program to be dropped. Can be a comma-delimited list.
`force`	If `force` is set to `FALSE`, the program must be unreferenced by any job otherwise an error will occur. If `force` is set to `TRUE`, all jobs referencing the program are disabled before dropping the program. Running jobs that point to the program are not affected by the `DROP_PROGRAM` call, and are allowed to continue.

program_name

The name of the program to be dropped. Can be a comma-delimited list.

force

If force is set to FALSE, the program must be unreferenced by any job otherwise an error will occur.

If force is set to TRUE, all jobs referencing the program are disabled before dropping the program.

Running jobs that point to the program are not affected by the DROP_PROGRAM call, and are allowed to continue.

Usage Notes

Dropping a program requires that you be the owner of the program or have ALTER privileges on that program. You can also drop a program if you have the CREATE ANY JOB privilege.

DROP_PROGRAM_ARGUMENT Procedures

This procedure drops a program argument. An argument can be specified by either name (if one has been given) or position.

The procedure is overloaded.

Syntax

Drops a program argument by position:

DBMS_SCHEDULER.DROP_PROGRAM_ARGUMENT (
   program_name            IN VARCHAR2,
   argument_position       IN PLS_INTEGER);

Drops a program argument by name:

DBMS_SCHEDULER.DROP_PROGRAM_ARGUMENT (
   program_name            IN VARCHAR2,
   argument_name           IN VARCHAR2);

Parameters

Table 93-31 DROP_PROGRAM_ARGUMENT Procedure Parameters

Parameter	Description
`program_name`	The name of the program to be altered. A program with this name must exist.
`argument_name`	The name of the argument being dropped
`argument_position`	The position of the argument to be dropped

Usage Notes

Dropping a program argument requires that you be the owner of the program or have ALTER privileges on that program. You can also drop a program argument if you have the CREATE ANY JOB privilege.

DROP_SCHEDULE Procedure

This procedure drops a schedule.

Syntax

DBMS_SCHEDULER.DROP_SCHEDULE (
   schedule_name    IN VARCHAR2,
   force            IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-32 DROP_SCHEDULE Procedure Parameters

Parameter Description

Parameter	Description
`schedule_name`	The name of the schedule. Can be a comma-delimited list.
`force`	If `force` is set to `FALSE`, the schedule must be unreferenced by any job or window otherwise an error will occur. If `force` is set to `TRUE`, any jobs or windows that use this schedule will be disabled before the schedule is dropped Running jobs and open windows that point to the schedule are not affected.

schedule_name

The name of the schedule. Can be a comma-delimited list.

force

If force is set to FALSE, the schedule must be unreferenced by any job or window otherwise an error will occur.

If force is set to TRUE, any jobs or windows that use this schedule will be disabled before the schedule is dropped

Running jobs and open windows that point to the schedule are not affected.

Usage Notes

You must be the owner of the schedule being dropped or have ALTER privileges for the schedule or the CREATE ANY JOB privilege.

DROP_WINDOW Procedure

This procedure drops a window. All metadata about the window is removed from the database. All references to the window are removed from window groups.

Syntax

DBMS_SCHEDULER.DROP_WINDOW (
   window_name             IN VARCHAR2,
   force                   IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-33 DROP_WINDOW Procedure Parameters

Parameter Description

Parameter	Description
`window_name`	The name of the window. Can be a comma-delimited list.
`force`	If `force` is set to `FALSE`, the window must be not be open or referenced by any job otherwise an error will occur. If `force` is set to `TRUE`, the window will be dropped and those jobs that have the window as their schedule will be disabled. However, jobs that have a window group of which the dropped window was a member as their schedule will not be disabled. If the window is open then, the Scheduler attempts to first close the window and then drop it. When the window is closed, normal close window rules apply. Running jobs that have the window as their schedule will be allowed to continue, unless the `stop_on_window_close` flag was set to `TRUE` for the job. If this is the case, the job will be stopped when the window is dropped.

window_name

The name of the window. Can be a comma-delimited list.

force

If force is set to FALSE, the window must be not be open or referenced by any job otherwise an error will occur.

If force is set to TRUE, the window will be dropped and those jobs that have the window as their schedule will be disabled. However, jobs that have a window group of which the dropped window was a member as their schedule will not be disabled. If the window is open then, the Scheduler attempts to first close the window and then drop it. When the window is closed, normal close window rules apply.

Running jobs that have the window as their schedule will be allowed to continue, unless the stop_on_window_close flag was set to TRUE for the job. If this is the case, the job will be stopped when the window is dropped.

Usage Notes

Dropping a window requires the MANAGE SCHEDULER privilege.

DROP_WINDOW_GROUP Procedure

This procedure drops a window group but not the windows that are members of this window group.

Syntax

DBMS_SCHEDULER.DROP_WINDOW_GROUP (
   group_name              IN VARCHAR2
   force                   IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-34 DROP_WINDOW_GROUP Procedure Parameters

Parameter Description

group_name

The name of the window group

force

If force is set to FALSE, the window group must be unreferenced by any job otherwise an error will occur.

If force is set to TRUE, the window group will be dropped and those jobs that have the window group as their schedule will be disabled. Running jobs that have the window group as their schedule are allowed to continue, even if the stop_on_window_close flag was set to TRUE when for the job.

If a member of the window group that is being dropped is open, the window group can still be dropped.

Usage Notes

If you want to drop all the windows that are members of this group but not the window group itself, you can use the DROP_WINDOW procedure and provide the name of the window group to the call.

To drop a window group, you must have the MANAGE SCHEDULER privilege.

ENABLE Procedure

This procedure enables a program, job, chain, window, or window group. When an object is enabled, the enabled flag is set to TRUE. By default, jobs, chains, and programs are created disabled and windows and window groups are created enabled.

Validity checks are performed before enabling an object. If the check fails, the object is not enabled, and an appropriate error is returned. This procedure does not return an error if the object was already enabled.

Syntax

DBMS_SCHEDULER.ENABLE (
   name              IN VARCHAR2);

Parameters

Table 93-35 ENABLE Procedure Parameters

Parameter Description

Parameter	Description
`name`	The name of the Scheduler object being enabled. Can be a comma-delimited list of names. If a job class name is specified, then all the jobs in the job class are enabled. If a window group name is specified, then the window group will be enabled, but the windows that are members of the window group, will not be enabled.

name

The name of the Scheduler object being enabled. Can be a comma-delimited list of names.

If a job class name is specified, then all the jobs in the job class are enabled.

If a window group name is specified, then the window group will be enabled, but the windows that are members of the window group, will not be enabled.

Usage Notes

Because the ENABLE procedure is used for several Scheduler objects, when enabling windows or window groups, they must be preceded by SYS.

To run ENABLE for a window or window group, you must have the MANAGE SCHEDULER privilege. Otherwise, you must be the owner of the object being enabled or have ALTER privileges on that object or have the CREATE ANY JOB privilege. For a job of type EXECUTABLE (or for a job that points to a program of type EXECUTABLE), the job owner must have the CREATE EXTERNAL JOB system privilege before the job can be enabled or run.

EVALUATE_CALENDAR_STRING Procedure

You can define repeat intervals of jobs, windows or schedules using the Scheduler's calendaring syntax. This procedure evaluates the calendar expression and tells you what the next execution date of a job or window will be. This is very useful for testing the correct definition of the calendar string without having to actually schedule the job or window.

This procedure can also be used to get multiple steps of the repeat interval by passing the next_run_date returned by one invocation as the return_date_after argument of the next invocation of this procedure.

Syntax

DBMS_SCHEDULER.EVALUATE_CALENDAR_STRING (
   calendar_string    IN  VARCHAR2,
   start_date         IN  TIMESTAMP WITH TIME ZONE,
   return_date_after  IN  TIMESTAMP WITH TIME ZONE,
   next_run_date      OUT TIMESTAMP WITH TIME ZONE);

Parameters

Table 93-36 EVALUATE_CALENDAR_STRING Procedure Parameters

Parameter	Description
`calendar_string`	The calendar string to be evaluated. The string must be in the calendaring syntax described in "Operational Notes".
`start_date`	The date after which the repeat interval becomes valid. It can also be used to fill in specific items that are missing from the calendar string. Can optionally be `NULL`.
`return_date_after`	With the `start_date` and the calendar string, the Scheduler has sufficient information to determine all valid execution dates. By setting this argument, the Scheduler knows which one of all possible matches to return. When a `NULL` value is passed for this argument, the Scheduler automatically fills in `systimestamp` as its value.
`next_run_date`	The first timestamp that matches the calendar string and start date that occurs after the value passed in for the `return_date_after` argument.

Examples

The following code fragment can be used to determine the next five dates a job will run given a specific calendar string.

SET SERVEROUTPUT ON;
ALTER SESSION set NLS_DATE_FORMAT = 'DD-MON-YYYY HH24:MI:SS';
Session altered.

DECLARE
start_date        TIMESTAMP;
return_date_after TIMESTAMP;
next_run_date     TIMESTAMP;
BEGIN
start_date :=
  to_timestamp_tz('01-JAN-2003 10:00:00','DD-MON-YYYY HH24:MI:SS');
return_date_after := start_date;
FOR i IN 1..5 LOOP
  DBMS_SCHEDULER.EVALUATE_CALENDAR_STRING(  
    'FREQ=DAILY;BYHOUR=9;BYMINUTE=30;BYDAY=MON,TUE,WED,THU,FRI',
    start_date, return_date_after, next_run_date);
DBMS_OUTPUT.PUT_LINE('next_run_date: ' || next_run_date);
return_date_after := next_run_date;
END LOOP;
END;
/

next_run_date: 02-JAN-03 09.30.00.000000 AM
next_run_date: 03-JAN-03 09.30.00.000000 AM
next_run_date: 06-JAN-03 09.30.00.000000 AM
next_run_date: 07-JAN-03 09.30.00.000000 AM
next_run_date: 08-JAN-03 09.30.00.000000 AM

PL/SQL procedure successfully completed.

Usage Notes

No specific Scheduler privileges are required.

EVALUATE_RUNNING_CHAIN Procedure

This procedure forces reevaluation of the rules of a running chain to trigger any rules for which the conditions have been satisfied. The job passed as an argument must point to a chain and must be running. If the job is not running, an error is thrown. (RUN_JOB can be used to start the job.)

If any of the steps of the chain are themselves running chains, another EVALUATE_RUNNING_CHAIN is performed on each of the nested running chains.

Syntax

DBMS_SCHEDULER.EVALUATE_RUNNING_CHAIN (
   job_name              IN VARCHAR2);

Parameters

Table 93-37 EVALUATE_RUNNING_CHAIN Procedure Parameter

Parameter	Description
`job_name`	The name of the running job (pointing to a chain) to reevaluate the rules for

Usage Notes

Running EVALUATE_RUNNING_CHAIN on a job requires alter privileges on the job (either by being the owner, or by having ALTER privileges on the job or by having the CREATE ANY JOB system privilege).

Note:

The Scheduler automatically evaluates a chain:

At the start of the chain job
When a chain step completes
When an event occurs that is associated with one of the event steps of the chain

For most chains, this is sufficient. EVALUATE_RUNNING_CHAIN should be used only under the following circumstances:

After manual intervention of a running chain with the ALTER_RUNNING_CHAIN procedure
When chain rules use SQL syntax and the rule conditions contain elements that are not under the control of the Scheduler.

In these cases, EVALUATE_RUNNING_CHAIN may not be needed if you set the evaluation_interval attribute when you created the chain.

GENERATE_JOB_NAME Function

This function returns a unique name for a job. The name will be of the form {prefix}N where N is a number from a sequence. If no prefix is specified, the generated name will, by default, be JOB$_1, JOB$_2, JOB$_3, and so on. If 'SCOTT' is specified as the prefix, the name will be SCOTT1, SCOTT2, and so on.

Syntax

DBMS_SCHEDULER.GENERATE_JOB_NAME (
   prefix        IN VARCHAR2 DEFAULT 'JOB$_') RETURN VARCHAR2;

Parameters

Table 93-38 GENERATE_JOB_NAME Function Parameter

Parameter	Description
`prefix`	The prefix to use when generating the job name

Usage Notes

If the prefix is explicitly set to NULL, the name will be just the sequence number. In order to successfully use such numeric names, they must be surrounded by double quotes throughout the DBMS_SCHEDULER calls. A prefix cannot be longer than 18 characters and cannot end with a digit.

Note that, even though the GENERATE_JOB_NAME function will never return the same job name twice, there is a small chance that the returned name matches an already existing database object.

No specific Scheduler privileges are required to use this function.

GET_ATTRIBUTE Procedure

This procedure retrieves the value of an attribute of a Scheduler object. It is overloaded to output values of the following types: VARCHAR2, TIMESTAMP WITH TIMEZONE, BOOLEAN, PLS_INTEGER, and INTERVAL DAY TO SECOND.

Syntax

DBMS_SCHEDULER.GET_ATTRIBUTE (
   name           IN VARCHAR2,
   attribute      IN VARCHAR2,
   value          OUT [VARCHAR2, TIMESTAMP WITH TIMEZONE, 
                     PLS_INTEGER, BOOLEAN, INTERVAL DAY TO SECOND);

DBMS_SCHEDULER.GET_ATTRIBUTE (
   name           IN VARCHAR2,
   attribute      IN VARCHAR2,
   value          OUT [VARCHAR2, TIMESTAMP WITH TIMEZONE,
                     PLS_INTEGER, BOOLEAN, INTERVAL DAY TO SECOND],
   value2         OUT VARCHAR2);

Parameters

Table 93-39 GET_ATTRIBUTE Procedure Parameters

Parameter	Description
`name`	The name of the object
`attribute`	The attribute being retrieved
`value`	The existing value of the attribute
`value2`	Most attributes have only one value associated with them, but some can have two. The `value2` argument is for this optional second value.

Usage Notes

To run GET_ATTRIBUTE for a job class, you must have the MANAGE SCHEDULER privilege or have EXECUTE privileges on the class. For a schedule, window, or a window group, no privileges are necessary. Otherwise, you must be the owner of the object or have ALTER or EXECUTE privileges on that object or have the CREATE ANY JOB privilege.

GET_SCHEDULER_ATTRIBUTE Procedure

This procedure retrieves the value of a Scheduler attribute.

Syntax

DBMS_SCHEDULER.GET_SCHEDULER_ATTRIBUTE (
   attribute      IN VARCHAR2,
   value          OUT VARCHAR2);

Parameters

Table 93-40 GET_SCHEDULER_ATTRIBUTE Procedure Parameters

Parameter	Description
`attribute`	The name of the attribute
`value`	The existing value of the attribute

Usage Notes

To run GET_SCHEDULER_ATTRIBUTE, you must have the MANAGE SCHEDULER privilege.

Table 93-41 lists the Scheduler attributes that you can retrieve. For more detail on these attributes, see Table 93-61 and the section "Configuring the Scheduler" in Oracle Database Administrator's Guide.

Table 93-41 Scheduler Attributes Retrievable with GET_SCHEDULER_ATTRIBUTE

Scheduler Attribute	Description
`default_timezone`	Default time zone used by the Scheduler for repeat intervals and windows
`log_history`	Retention period in days for job and window logs
`max_job_slave_processes`	Maximum number of job slave processes that the Scheduler can start. May be `NULL`.
`current_open_window`	Name of the currently open window
`event_expiry_time`	Time in seconds before an event generated by the Scheduler and enqueued onto the Scheduler event queue expires. May be `NULL`.

OPEN_WINDOW Procedure

This procedure opens a window independent of its schedule. This window will open and the resource plan associated with it, will take effect immediately for the duration specified or for the normal duration of the window if no duration is given. Only an enabled window can be manually opened.

Syntax

DBMS_SCHEDULER.OPEN_WINDOW (
   window_name             IN VARCHAR2,
   duration                IN INTERVAL DAY TO SECOND,
   force                   IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-42 OPEN_WINDOW Procedure Parameters

Parameter Description

window_name

The name of the window

duration

The duration of the window. It is of type interval day to second. If it is NULL, then the window will be opened for the regular duration as specified in the window metadata.

force

If force is set to FALSE, opening an already open window, will generate an error.

If force is set to TRUE:

You can open a window that is already open. The window stays open for the duration specified in the call, from the time the OPEN_WINDOW command was issued. Consider an example to illustrate this. window1 was created with a duration of four hours. It has how been open for two hours. If at this point you reopen window1 using the OPEN_WINDOW call and do not specify a duration, then window1 will be open for another four hours because it was created with that duration. If you specified a duration of 30 minutes, the window will close in 30 minutes.

The Scheduler automatically closes any window that is open at that time, even if it has a higher priority. For the duration of this manually opened window, the Scheduler does not open any other scheduled windows even if they have a higher priority.

Usage Notes

If there are jobs running when the window opens, the resources allocated to them might change due to the switch in resource plan.

Opening a window manually has no impact on regular scheduled runs of the window. The next open time of the window is not updated, and will be as determined by the regular scheduled opening.

When a window that was manually opened closes, the rules about overlapping windows are applied to determine which other window should be opened at that time if any at all.

If a window fails to switch resource plans because the designated resource plan no longer exists or because resource plan switching by windows is disabled (for example, by using the ALTER SYSTEM statement with the force option), the failure to switch resource plans is recorded in the window log.

Opening a window requires the MANAGE SCHEDULER privilege.

PURGE_LOG Procedure

By default, the Scheduler automatically purges all rows in the job log and window log that are older than 30 days. The PURGE_LOG procedure is used to purge additional rows from the job and window log.

Rows in the job log table pertaining to the steps of a chain are purged only when the entry for the main chain job is purged (either manually or automatically).

Syntax

DBMS_SCHEDULER.PURGE_LOG (
   log_history             IN PLS_INTEGER  DEFAULT 0,
   which_log               IN VARCHAR2     DEFAULT 'JOB_AND_WINDOW_LOG',
   job_name                IN VARCHAR2     DEFAULT NULL);

Parameters

Table 93-43 PURGE_LOG Procedure Parameters

Parameter	Description
`log_history`	This specifies how much history (in days) to keep. The valid range is 0 - 999. If set to 0, no history is kept.
`which_log`	This specifies which type of log. Valid values for `which_log` are `job_log`, `window_log`, and `job_and_window_log`.
`job_name`	This specifies which job-specific entries must be purged from the jog log. This can be a comma-delimited list of job names and job classes. Whenever `job_name` has a value other than `NULL`, the `which_log` argument implicitly includes the job log.

Usage Notes

This procedure requires the MANAGE SCHEDULER privilege.

Examples

The following will completely purge all rows from both the job log and the window log:

DBMS_SCHEDULER.PURGE_LOG();

The following will purge all rows from the window log that are older than 5 days:

DBMS_SCHEDULER.PURGE_LOG(5, 'window_log');

The following will purge all rows from the window log that are older than 1 day and all rows from the job log that are related to jobs in jobclass1 and that are older than 1 day:

DBMS_SCHEDULER.PURGE_LOG(1, 'job_and_window_log', 'sys.jobclass1');

REMOVE_EVENT_QUEUE_SUBSCRIBER Procedure

This procedure unsubscribes a user from the Scheduler event queue SYS.SCHEDULER$_EVENT_QUEUE.

Syntax

DBMS_SCHEDULER.REMOVE_EVENT_QUEUE_SUBSCRIBER (
   subscriber_name         IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-44 REMOVE_EVENT_QUEUE_SUBSCRIBER Procedure Parameters

Parameter	Description
`subscriber_name`	Name of the Oracle Streams Advanced Queuing (AQ) agent for which to remove the subscription. If `NULL`, the user name of the calling user is used.

Usage Notes

After the agent is unsubscribed, it is deleted. If the agent does not exist or is not currently subscribed to the Scheduler event queue, an error is raised.

REMOVE_WINDOW_GROUP_MEMBER Procedure

This procedure removes one or more windows from an existing window group.

Syntax

DBMS_SCHEDULER.REMOVE_WINDOW_GROUP_MEMBER (
   group_name              IN VARCHAR2,
   window_list             IN VARCHAR2);

Parameters

Table 93-45 REMOVE_WINDOW_GROUP_MEMBER Procedure Parameters

Parameter	Description
`group_name`	The name of the window group.
`window_list`	The name of the window or windows.

Usage Notes

If any of the windows specified is either invalid, does not exist, or is not a member of the given group, the call fails. Removing a window from a group requires the MANAGE SCHEDULER privilege.

Dropping an open window from a window group has no impact on running jobs that has the window as its schedule since the jobs would only be stopped when a window closes.

RESET_JOB_ARGUMENT_VALUE Procedures

This procedure resets (clears) the value previously set to an argument for a job.

RESET_JOB_ARGUMENT_VALUE is overloaded.

Syntax

Clears a previously set job argument value by argument position:

DBMS_SCHEDULER.RESET_JOB_ARGUMENT_VALUE (
   job_name                IN VARCHAR2,
   argument_position       IN PLS_INTEGER);

Clears a previously set job argument value by argument name:

DBMS_SCHEDULER.RESET_JOB_ARGUMENT_VALUE (
   job_name                IN VARCHAR2,
   argument_name           IN VARCHAR2);

Parameters

Table 93-46 RESET_JOB_ARGUMENT_VALUE Procedure Parameters

Parameter	Description
`job_name`	The name of the job being altered
`argument_position`	The position of the program argument being reset
`argument_name`	The name of the program argument being reset

Usage Notes

If the corresponding program argument has no default value, the job will be disabled. Resetting a program argument of a job belonging to another user requires ALTER privileges on that job. Arguments can be specified by position or by name.

RESET_JOB_ARGUMENT_VALUE requires that you be the owner of the job or have ALTER privileges on that job. You can also reset a job argument value if you have the CREATE ANY JOB privilege.

RUN_CHAIN Procedures

This procedure immediately runs a chain or part of a chain by creating a run-once job with the job name given. If no job_name is given, one will be generated of the form RUN_CHAIN$_chainnameN, where chainname is the first 8 characters of the chain name and N is an integer.If a list of start steps is given, only those steps will be started when the chain begins running. Steps not in the list that would normally have started are skipped and paused (so that they or the steps after them do not run). If start_steps is NULL, then the chain will start normally—that is, an initial evaluation will be done to see which steps to start running).

If a list of initial step states is given, the newly created chain job sets every listed step to the state specified for that step before evaluating the chain rules to see which steps to start. (Steps in the list are not started.)

Syntax

Runs a chain, with a list of start steps.

DBMS_SCHEDULER.RUN_CHAIN (
   chain_name                IN VARCHAR2,
   start_steps               IN VARCHAR2,
   job_name                  IN VARCHAR2 DEFAULT NULL);

Runs a chain, with a list of initial step states.

DBMS_SCHEDULER.RUN_CHAIN (
   chain_name               IN VARCHAR2, 
   step_state_list          IN SYS.SCHEDULER$_STEP_TYPE_LIST, 
   job_name                 IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-47 RUN_CHAIN Procedure Parameters

Parameter	Description
`chain_name`	The name of the chain to run
`job_name`	The name of the job to create to run the chain
`start_steps`	Comma-separated list of the steps to start when the chain starts running
`step_state_list`	List of chain steps with an initial state (`SUCCEEDED` or `FAILED`) to set for each. The list is provided as nested table type `SYS.SCHEDULER$_STEP_TYPE_LIST`, where each element is of type `SYS.SCHEDULER$_STEP_TYPE`. CREATE TYPE sys.scheduler$_step_type as object ( step_name varchar2(32), step_type varchar2(32)); CREATE TYPE sys.scheduler$_step_type_list IS TABLE OF sys.scheduler$_step_type; Set the attributes of `sys.scheduler$_step_type` as follows: `step_name` The name of the step `step_type` '`SUCCEEDED`' or '`FAILED` `error_number`' where error_number is a positive or negative integer.

Usage Notes

Running a chain requires CREATE JOB if the job is being created in the user's schema, or CREATE ANY JOB otherwise. In addition, the owner of the job being created needs execute privileges on the chain (by being the owner of the chain, by having the EXECUTE privilege on the chain, or by having the EXECUTE ANY PROGRAM system privilege).

Examples

The following example illustrates how to start a chain in the middle by providing the initial state of some chain steps.

declare
  initial_step_states sys.scheduler$_step_type_list;
begin
  initial_step_states := sys.scheduler$_step_type_list(
    sys.scheduler$_step_type('step1', 'SUCCEEDED'),
    sys.scheduler$_step_type('step2', 'FAILED 27486'),
    sys.scheduler$_step_type('step3', 'SUCCEEDED'),
    sys.scheduler$_step_type('step5', 'SUCCEEDED'));
  dbms_scheduler.run_chain('my_chain', initial_step_states);
end;
/

RUN_JOB Procedure

This procedure runs a job immediately.

Syntax

DBMS_SCHEDULER.RUN_JOB (
   job_name                IN VARCHAR2,
   use_current_session     IN BOOLEAN DEFAULT TRUE);

Parameters

Table 93-48 RUN_JOB Procedure Parameters

Parameter Description

job_name

The name of the job being run

use_current_session

This specifies whether the job run should occur in the same session as the one that the procedure was invoked from.

When use_current_session is set to TRUE:

You can test a job and see any possible errors on the command line.
run_count, last_start_date, last_run_duration, and failure_count are not updated.
RUN_JOB can be run in parallel with a regularly scheduled job run.

When use_current_session is set to FALSE:

You need to check the job log to find error information.
run_count, last_start_date, last_run_duration, and failure_count are updated.
RUN_JOB fails if a regularly scheduled job is running.

Usage Notes

The job does not have to be enabled. If the job is disabled, the following validity checks are performed before running it:

The job points to a valid job class.The job owner has EXECUTE privileges on the job class.If a program or chain is referenced, the program/chain exists.If a program or chain is referenced, the job owner has privileges to execute the program/chain.All argument values have been set (or have defaults).The job owner has the CREATE EXTERNAL JOB privilege if this is an external job.

The job can be run in two different modes. One is in the current user session. In this case, the call to RUN_JOB will block until it has completed the job. Any errors that occur during the execution of the job will be returned as errors to the RUN_JOB procedure. The other option is to run the job immediately like a regular job. In this case, RUN_JOB returns immediately and the job will be picked up by the coordinator and passed on to a job slave for execution. The Scheduler views and logs must be queried for the outcome of the job.

Multiple user sessions can use RUN_JOB in their sessions simultaneously when use_current_session is set to TRUE.

When using RUN_JOB with jobs that point to chains, use_current_session must be FALSE.

RUN_JOB requires that you be the owner of the job or have ALTER privileges on that job. You can also run a job if you have the CREATE ANY JOB privilege.

SET_ATTRIBUTE Procedure

This procedure changes an attribute of an object. It is overloaded to accept values of the following types: VARCHAR2, TIMESTAMP WITH TIMEZONE, BOOLEAN, PLS_INTEGER, and INTERVAL DAY TO SECOND. To set an attribute to NULL, the SET_ATTRIBUTE_NULL procedure should be used. What attributes can be set depends on the object being altered. With the exception of the object name, all object attributes can be changed.

SET_ATTRIBUTE is overloaded.

Syntax

DBMS_SCHEDULER.SET_ATTRIBUTE (
   name           IN VARCHAR2,
   attribute      IN VARCHAR2,
   value          IN [VARCHAR2, TIMESTAMP WITH TIMEZONE, 
                      PLS_INTEGER, BOOLEAN, INTERVAL DAY TO SECOND]);

DBMS_SCHEDULER.SET_ATTRIBUTE (
   name           IN VARCHAR2,
   attribute      IN VARCHAR2,
   value          IN [VARCHAR2, TIMESTAMP WITH TIMEZONE,
                      PLS_INTEGER, BOOLEAN, INTERVAL DAY TO SECOND],
   value2         IN VARCHAR2 DEFAULT NULL);

Parameters

Table 93-49 SET_ATTRIBUTE Procedure Parameters

Parameter	Description
`name`	The name of the object
`attribute`	See Table 93-50 through Table 93-57.
`value`	The new value being set for the attribute. This cannot be `NULL`. To set an attribute value to `NULL`, use the `SET_ATTRIBUTE_NULL` procedure.
`value2`	Most attributes have only one value associated with them, but some can have two. The `value2` argument is for this optional second value.

Usage Notes

If an object is altered and it was in the enabled state, the Scheduler will first disable it, make the change and then re-enable it. If any errors are encountered during the enable process, the object is not re-enabled and an error is generated.

If an object is altered and it was in the disabled state, it will remain disabled after it is altered.

To run SET_ATTRIBUTE for a window, window group, or job class, you must have the MANAGE SCHEDULER privilege. Otherwise, you must be the owner of the object being altered or have ALTER privileges on that object or have the CREATE ANY JOB privilege.

Job

If there is a running instance of the job when the SET_ATTRIBUTE call is made, it is not affected by the call. The change is only seen in future runs of the job.

If any of the schedule attributes of a job are altered while the job is running, the time of the next job run will be scheduled using the new schedule attributes. Schedule attributes of a job include schedule_name, start_date, end_date, and repeat_interval.

If any of the program attributes of a job are altered while the job is running, the new program attributes will take effect the next time the job runs. Program attributes of a job include program_name, job_action, job_type, and number_of_arguments. This is also the case for job argument values that have been set.

Granting ALTER on a job will let a user alter all attributes of that job except its program attributes (program_name, job_type, job_action, program_action, and number_of_arguments) and will not allow a user to use a PL/SQL expression to specify the schedule for a job.

We recommend you not to alter a job that was automatically created for you by the database. Jobs that were created by the database have the column SYSTEM set to TRUE in job views.

Program

If any currently running jobs use the program that is altered, they will continue to run with the program definition prior to the alter. The job will run with the new program definition the next time the job executes.

Schedule

If a schedule is altered, the change will not affect running jobs and open windows that use this schedule. The change will only be in effect the next time the jobs runs or the window opens.

Job Class

With the exception of the default job class, all job classes can be altered. To alter a job class, you must have the MANAGE SCHEDULER privilege.

When a job class is altered, running jobs that belong to the class are not affected. The change only takes effect for jobs that have not started running yet.

Window

When a window is altered, it does not affect an active window. The changes only take effect the next time the window opens.

To change resource plans, you must first set the RESOURCE_MANAGER_PLAN initialization parameter in the init.ora file or issue an ALTER SYSTEM SET RESOURCE_MANAGER_PLAN = my_plan statement before the window opens.

Job Attribute Values

Table 93-50 lists job attribute values.

Note:

See the CREATE_JOB procedure for more complete descriptions of the attributes in this table.

Table 93-50 Job Attribute Values

Name	Description
`logging_level`	This attribute specifies how much information is logged. The three possible options are: `DBMS_SCHEDULER.LOGGING_OFF` No logging will be performed for any jobs in this class. `DBMS_SCHEDULER.LOGGING_RUNS` The Scheduler will write detailed information to the job log for all runs of each job in this class. `DBMS_SCHEDULER.LOGGING_FULL` In addition to recording every run of a job, the Scheduler will record all operations performed on all jobs in this class. In other words, every time a job is created, enabled, disabled, altered, and so on will be recorded in the log.
`restartable`	This attribute specifies whether a job can be restarted in case of failure. By default, jobs are not restartable and this attribute is set to `FALSE`. Setting this to `TRUE` means that if a job fails while running, it will be restarted from the beginning point of the job. In the case of a chain job, if this attribute is `TRUE`, the chain is restarted from the beginning after an application failure. If this attribute is `FALSE`, or if there has been a database failure, the chain is restarted at the last running step. The `restart_on_recovery` attribute of that step then determines if the step is restarted or marked as stopped. (If marked as stopped, the chain evaluates rules and continues.) Note that setting this attribute to `TRUE` might lead to data inconsistencies in some situations, for example, if data is committed within a job. Retries on errors are not counted as regular runs. The run count or failure count is not incremented until the job succeeds or has failed all its six retries. The restartable attribute is used by the Scheduler to determine whether to retry the job not only on regular application errors, but after a database malfunction as well. The Scheduler will retry the job a maximum of six times. The first time, it will wait for one second and multiply this wait time with a factor of 10 each time thereafter. Both the run count and failure count are incremented by 1 if the job has failed all its six retries. If the job immediately succeeds, or it succeeds on one of its retries, run count is incremented by 1. The Scheduler will stop retrying a job when: One of the retries succeeds. All of its six retries have failed. The next retry would occur after the next regularly scheduled run of the job. The Scheduler no longer retries the job if the next scheduled retry is past the next regularly scheduled run for repeating jobs.
`max_failures`	This attribute specifies the number of times a job can fail on consecutive scheduled runs before it is automatically disabled. Once a job is disabled, it is no longer executed and its `STATE` is set to `BROKEN` in the `*_SCHEDULER_JOB` views. `max_failures` can be an integer between 1 to 1,000,000. By default, it is set to `NULL`, which indicates that new instances of the job will be started regardless of how many previous instances have failed.
`max_runs`	This attribute specifies the maximum number of consecutive scheduled runs of the job. Once `max_runs` is reached, the job is disabled and its state is changed to `COMPLETED`. `max_runs` can be an integer between 1 and 1,000,000. By default, it is set to `NULL`, which means that it will repeat forever or until `end_date` or `max_failures` is reached.
`max_run_duration`	This attribute specifies the maximum amount of time that the job should be allowed to run. Its datatype is `INTERVAL` `DAY` `TO` `SECOND`. If this attribute is set to a non-zero and non-`NULL` value, and job duration exceeds this value, the Scheduler raises an event of type `JOB_OVER_MAX_DUR`. It is then up to your event handler to decide whether or not to allow the job to continue.
`job_weight`	This attribute is for expert users of parallel technology only. If your job will be using parallel technology, you can set the value of this attribute to the degree of parallelism of your SQL inside the job. `job_weight` has a range of 1-100, with 1 being the default
`instance_stickiness`	This attribute should only be used for a database running in RAC mode. By default, it is set to `TRUE`. If you set `instance_stickiness` to `TRUE`, jobs start running on the instance with the lightest load and the Scheduler thereafter attempts to run on the instance that it last ran on. If that instance is either down or so overloaded that it will not start new jobs for a significant period of time, another instance will run the job. If the interval between runs is large, `instance_stickiness` will be ignored an the job will be handled as if it were a non-sticky job. If `instance_stickiness` is set to `FALSE`, each instance of the job runs on the first instance available. For non-RAC environments, this attribute is not useful because there is only one instance.
`stop_on_window_close`	This attribute only applies if the schedule of a job is a window or a window group. Setting this attribute to `TRUE` implies that the job should be stopped once the associated window is closed. The job is stopped using the `stop_job` procedure with force set to `FALSE`. By default, `stop_on_window_close` is set to `FALSE`. Therefore, if you do not set this attribute, the job will be allowed to continue after the window closes. Note that, although the job is allowed to continue, its resource allocation will probably change because closing a window generally also implies a change in resource plans.
`job_priority`	This attribute specifies the priority of this job relative to other jobs in the same class as this job. If multiple jobs within a class are scheduled to be executed at the same time, the job priority determines the order in which jobs from that class are picked up for execution by the job coordinator. It can be a value from 1 through 5, with 1 being the first to be picked up for job execution. If no job priority is specified when creating a job, the default priority of 3 is assigned to it.
`schedule_limit`	In heavily loaded systems, jobs are not always started at their scheduled time. This attribute enables you to have the Scheduler not start a job at all if the delay in starting the job is larger than the interval specified. It can be a value of 1 minute to 99 days. For example, if a job was supposed to start at noon and the schedule limit is set to 60 minutes, the job will not be run if it has not started to run by 1:00 p.m. If `schedule_limit` is not specified, the job is executed at some later date as soon as there are resources available to run it. By default, this attribute is set to null, which indicates that the job can be run at any time after its scheduled time. A scheduled job run that is skipped because of this attribute does not count against the number of runs and failures of the job. An entry in the job log will be made to reflect the skipped run.
`program_name`	The name of a program object to use with this job. If this is set, `job_action`, `job_type` and `number_of_arguments` should be `NULL`.
`job_action`	The action that the job performs, depending on the `job_type` attribute. For example, if `job_type` is '`STORED_PROCEDURE`', `job_action` contains the name of the stored procedure.
`job_type`	The type of this job. Can be any of: '`PLSQL_BLOCK`', '`STORED_PROCEDURE`', '`EXECUTABLE`', and '`CHAIN`'. If this is set, `program_name` must be `NULL`.
`number_of_arguments`	The number of arguments if the program is inlined. If this is set, `program_name` should be `NULL`.
`schedule_name`	The name of a schedule or window or window group to use as the schedule for this job. If this is set, `end_date`, `start_date` and `repeat_interval` should all be `NULL`.
`repeat_interval`	Either a PL/SQL function returning the next date on which to run, or calendaring syntax expression. If this is set, `schedule_name` should be `NULL`. See "Calendaring Syntax" for more information.
`start_date`	The original date on which this job started or will be scheduled to start. If this is set, `schedule_name` should be `NULL`.
`end_date`	The date after which the job will no longer run. It will be dropped if `auto_drop` is set or disabled with the state changed to `COMPLETED` if it is. If this is set, `schedule_name` should be `NULL`.
`job_class`	The class this job is associated with.
`comments`	An optional comment.
`auto_drop`	Whether the job should be dropped after having completed.
`event_spec`	This attribute takes two values: the `value` argument should contain the event condition and the `value2` argument should contain the queue specification. For details on what these arguments should contain, see the descriptions for the `event_condition` and `queue_spec` arguments in the `CREATE_JOB` procedure.
`raise_events`	This attribute tells the Scheduler at what stages of the job's execution events should be raised. It is a bit vector in which zero or more of the following bits can be set. Each bit has a package constant corresponding to it. `job_started CONSTANT PLS_INTEGER := 1` `job_succeeded CONSTANT PLS_INTEGER := 2` `job_failed CONSTANT PLS_INTEGER :=4` `job_broken CONSTANT PLS_INTEGER :=8` `job_completed CONSTANT PLS_INTEGER :=16` `job_stopped CONSTANT PLS_INTEGER :=32` `job_sch_lim_reached CONSTANT PLS_INTEGER :=64` `job_disabled CONSTANT PLS_INTEGER :=128` `job_chain_stalled CONSTANT PLS_INTEGER :=256` `job_all_events CONSTANT PLS_INTEGER := 511` `job_run_completed CONSTANT PLS_INTEGER := job_succeeded + job_failed + job_stopped` Table Table 93-51 describes these event types in detail.

Table 93-51 Event Types Raised by the Scheduler

Event Type	Description
`job_started`	The job started
`job_succeeded`	The job completed successfully
`job_failed`	The job failed, either by throwing an error or by abnormally terminating
`job_broken`	The job has been disabled and has changed to the `BROKEN` state because it exceeded the number of failures defined by the `max_failures` job attribute
`job_completed`	The job completed because it reached its `max_runs` or `end_date`
`job_stopped`	The job was stopped by a call to `STOP_JOB`
`job_sch_lim_reached`	The job's schedule limit was reached. The job was not started because the delay in starting the job exceeded the value of the `schedule_limit` job attribute.
`job_disabled`	The job was disabled by the Scheduler or by a call to `SET_ATTRIBUTE`
`job_chain_stalled`	A job running a chain was put into the `CHAIN_STALLED` state. A running chain becomes stalled if there are no steps running or scheduled to run and the chain `evaluation_interval` is set to `NULL`. No progress will be made in the chain unless there is manual intervention.
`job_all_events`	Not an event, but a constant that provides an easy way for you to enable all events
`job_run_completed`	A job run either failed, succeeded, or was stopped

Program Attribute Values

Table 93-52 lists program attribute values.

Note:

See the CREATE_PROGRAM procedure for more complete descriptions of the attributes in this table.

Table 93-52 Program Attribute Values

Name	Description
`program_action`	The action that the program performs, depending on the `program_type` attribute. For example, if `program_type` is '`STORED_PROCEDURE`', `program_action` contains the name of the stored procedure.
`program_type`	The type of program. This must be one of the following supported program types: '`PLSQL_BLOCK`', '`STORED_PROCEDURE`', and '`EXECUTABLE`'.
`number_of_arguments`	The number of arguments required by the stored procedure or other executable that the program invokes
`comments`	An optional comment. This can describe what the program does, or give usage details.

Job Class Values

Table 93-53 lists job class attribute values.

Note:

See the CREATE_JOB_CLASS procedure for more complete descriptions of the attributes in this table.

Table 93-53 Job Class Attribute Values

Name	Description
`resource_consumer_group`	The resource consumer group a class is associated with. If `resource_consumer_group` is set, service must be `NULL`.
`service`	The database service that the jobs in the job class have affinity to. If service is set, `resource_consumer_group` must be `NULL`.
`logging_level`	This attribute specifies how much information is logged. The three possible options are: `DBMS_SCHEDULER.LOGGING_OFF` No logging will be performed for any jobs in this class. `DBMS_SCHEDULER.LOGGING_RUNS` The Scheduler will write detailed information to the job log for all runs of each job in this class. `DBMS_SCHEDULER.LOGGING_FULL` In addition to recording every run of a job, the Scheduler will record all operations performed on all jobs in this class. In other words, every time a job is created, enabled, disabled, altered, and so on will be recorded in the log.
`log_history`	This enables you to control the amount of logging the Scheduler performs. To prevent the job log and the window log from growing indiscriminately, the Scheduler has an attribute that specifies how much history (in days) to keep. Once a day, the Scheduler will automatically purge all log entries from both the job log as well as the window log that are older than the specified history. The default is 30 days. You can change the default by using the `SET_SCHEDULER_ATTRIBUTE` procedure. For example, to change it to 90 days, issue the following statement: `DBMS_SCHEDULER.SET_SCHEDULER_ATTRIBUTE ('log_history','90');` The range of valid values is 1 through 999.
`comments`	An optional comment about the class.

Window Attribute Values

Table 93-54 lists window attribute values.

Note:

See the CREATE_WINDOW procedure for more complete descriptions of the attributes in this table.

Table 93-54 Window Attribute Values

Name	Description
`resource_plan`	The resource plan to be associated with a window. When the window opens, the system will switch to this resource plan. When the window closes, the original resource plan will be restored. If a resource plan has been made active with the `force` option, no resource plan switch will occur. Only one resource plan can be associated with a window. It may be `NULL` or the empty string (""). When it is `NULL`, the resource plan that is in effect when the window opens stays in effect for the duration of the window. When it is the empty string, the resource manager is disabled for the duration of the window.
`window_priority`	The priority of the window. Must be one of '`LOW`' (default) or '`HIGH`'.
`duration`	The duration of the window.
`schedule_name`	The name of a schedule to use with this window. If this is set, `start_date`, `end_date`, and `repeat_interval` must all be `NULL`.
`repeat_interval`	A string using the calendaring syntax. PL/SQL date functions are not allowed. If this is set, `schedule_name` must be `NULL`. See "Calendaring Syntax" for more information.
`start_date`	The next date on which this window is scheduled to open. If this is set, `schedule_name` must be `NULL`.
`end_date`	The date after which the window will no longer open. If this is set, `schedule_name` must be `NULL`.
`comments`	An optional comment about the window.

Window Group Attribute Values

Table 93-55 lists window group attribute values.

Table 93-55 Window Group Attribute Values

Name	Description
`comments`	An optional comment about the window group.

Schedule Attribute Values

Table 93-56 lists schedule attribute values.

Note:

See the CREATE_SCHEDULE and CREATE_CALENDAR_SCHEDULE procedures for more complete descriptions of the attributes in this table.

Table 93-56 Schedule Attribute Values

Name	Description
`repeat_interval`	An expression using the calendaring syntax. See "Calendaring Syntax" for more information.
`comments`	An optional comment.
`end_date`	The cutoff date after which the schedule will not specify any dates.
`start_date`	The start or reference date used by the calendaring syntax.
`event_spec`	This attribute takes two values: the `value` argument should contain the event condition and the `value2` argument should contain the queue specification. For details on what these arguments should contain, see the descriptions for the `event_condition` and `queue_spec` arguments to the `CREATE_JOB` procedure.

Chain Attribute Values

Table 93-57 lists chain attribute values.

Note:

See the CREATE_CHAIN procedure for more complete descriptions of the attributes in this table.

Table 93-57 Chain Attribute Values

Name Description

evaluation_interval

If this is not NULL, evaluation of the chain occurs not only at normal evaluation times (when the job starts, when a step completes, or when an event that is associated with an event step arrives), but also periodically at this interval.

For most chains, the normal evaluation times are sufficient. Because evaluation of a large chain is CPU intensive, this attribute should be used only when chain rules use SQL syntax and the rule conditions contain elements that are not under the control of the Scheduler.

comments

An optional comment describing the purpose of the chain.

SET_ATTRIBUTE_NULL Procedure

This procedure sets an attribute of an object to NULL. What attributes can be set depends on the object being altered. If the object is enabled, it will be disabled before being altered and be reenabled afterward. If the object cannot be reenabled, an error is generated and the object will be left in a disabled state.

Syntax

DBMS_SCHEDULER.SET_ATTRIBUTE_NULL (
   name              IN VARCHAR2,
   attribute         IN VARCHAR2);

Parameters

Table 93-58 SET_ATTRIBUTE_NULL Procedure Parameters

Parameter	Description
`name`	The name of the object
`attribute`	The attribute being changed

Usage Notes

To run SET_ATTRIBUTE_NULL for a window, window group, or job class, you must have the MANAGE SCHEDULER privilege. Otherwise, you must be the owner of the object being altered or have ALTER privileges on that object or have the CREATE ANY JOB privilege.

SET_JOB_ANYDATA_VALUE Procedures

This procedure sets the value for an argument of the associated program for a job, encapsulated in an AnyData object. It overrides any default value set for the program argument. NULL is a valid assignment for a program argument. The argument can be specified by position or by name. You can specify by name only when:

The job points to a saved program object
The argument was assigned a name with the DEFINE_ANYDATA_ARGUMENT Procedure

No type checking of the argument is done at any time by the Scheduler.

SET_JOB_ANYDATA_VALUE is overloaded.

Syntax

Sets a program argument by its position.

DBMS_SCHEDULER.SET_JOB_ANYDATA_VALUE (
   job_name                IN VARCHAR2,
   argument_position       IN PLS_INTEGER,
   argument_value          IN SYS.ANYDATA);

Sets a program argument by its name.

DBMS_SCHEDULER.SET_JOB_ANYDATA_VALUE (
   job_name                IN VARCHAR2,
   argument_name           IN VARCHAR2,
   argument_value          IN SYS.ANYDATA);

Parameters

Table 93-59 SET_JOB_ANYDATA_VALUE Procedure Parameters

Parameter	Description
`job_name`	The name of the job to be altered
`argument_name`	The name of the program argument being set
`argument_position`	The position of the program argument being set
`argument_value`	The new value to be assigned to the program argument, encapsulated in an `AnyData` object

Usage Notes

SET_JOB_ANYDATA_VALUE requires that you be the owner of the job or have ALTER privileges on that job. You can also set a job argument value if you have the CREATE ANY JOB privilege.

See Also:

"SET_JOB_ARGUMENT_VALUE Procedures"
"DEFINE_ANYDATA_ARGUMENT Procedure"

SET_JOB_ARGUMENT_VALUE Procedures

This procedure sets the value of an argument of the associated program for a job. It overrides any default value set for the program argument. NULL is a valid assignment for a program argument. The argument can be specified by position or by name. You can specify by name only when:

The job points to a saved program object
The argument was assigned a name with the DEFINE_PROGRAM_ARGUMENT Procedures or the DEFINE_METADATA_ARGUMENT Procedure

No type checking of the argument is done at any time by the Scheduler.

SET_JOB_ARGUMENT_VALUE is overloaded.

Syntax

Sets an argument value by position:

DBMS_SCHEDULER.SET_JOB_ARGUMENT_VALUE (
   job_name                IN VARCHAR2,
   argument_position       IN PLS_INTEGER,
   argument_value          IN VARCHAR2);

Sets an argument value by name:

DBMS_SCHEDULER.SET_JOB_ARGUMENT_VALUE (
   job_name                IN VARCHAR2,
   argument_name           IN VARCHAR2,
   argument_value          IN VARCHAR2);

Parameters

Table 93-60 SET_JOB_ARGUMENT_VALUE Procedure Parameters

Parameter	Description
`job_name`	The name of the job to be altered
`argument_name`	The name of the program argument being set
`argument_position`	The position of the program argument being set
`argument_value`	The new value to be set for the program argument. To set a non-`VARCHAR` value, use the `SET_JOB_ANYDATA_ARGUMENT_VALUE` procedure.

Usage Notes

SET_JOB_ARGUMENT_VALUE requires that you be the owner of the job or have ALTER privileges on that job. You can also set a job argument value if you have the CREATE ANY JOB privilege.

See Also:

"SET_JOB_ANYDATA_VALUE Procedures"
"DEFINE_PROGRAM_ARGUMENT Procedures"

SET_SCHEDULER_ATTRIBUTE Procedure

This procedure sets the value of a Scheduler attribute. This takes effect immediately but the resulting changes may not be seen immediately. The attributes you can set are default_timezone, max_job_slave_processes, and log_history.

Syntax

DBMS_SCHEDULER.SET_SCHEDULER_ATTRIBUTE (
   attribute      IN VARCHAR2,
   value          IN VARCHAR2);

Parameters

Table 93-61 SET_SCHEDULER_ATTRIBUTE Procedure Parameters

Parameter Description

attribute

The name of the Scheduler attribute. Possible values are:

default_timezone: It is very important that this attribute is set. Whenever a repeat_interval is specified without setting the start_date, the Scheduler needs to know which time zone it must apply to the repeat interval syntax. For example, if the repeat interval is specified as
```
"FREQ=DAILY;BYHOUR=22"
```
the job will repeat every day at 10pm, but 10pm in which time zone? If no start_date is specified the Scheduler will pick up the time zone from this default_timezone attribute. If you want your job or window to follow daylight savings adjustments, you must set this attribute to the proper region name. For instance, if your database resides in Paris, you would set this to 'Europe/Warsaw'.

Daylight saving adjustments will not be followed if you specify an absolute offset. For example, '-8:00' would be correct for only half of the year in San Francisco. If no value is specified for this attribute, the Scheduler uses the time zone of systimestamp when the job or window is enabled. This is always an absolute offset and will not follow daylight savings adjustments.
log_history: This enables you to control the amount of logging the Scheduler performs.
max_job_slave_processes: This enables you to set a maximum number of slave processes for a particular system configuration and load. The default value is NULL, and the valid range is 1-999.

Even though the Scheduler automatically determines what the optimum number of slave processes is for a given system configuration and load, you still might want to set a fixed limit on the Scheduler. If this is the case, you can set this attribute.

Although the number set by max_job_slave_processes is a real maximum, it does not mean the Scheduler will start the specified number of slaves. For example, even though this attribute is set to 10, the Scheduler might still determine that is should not start more than 3 slave processes. However, if it wants to start 15, but it is set to 10, it will not start more than 10.
event_expiry_time: The time in seconds before an event generated by the Scheduler (in other words, a message enqueued by the Scheduler into the Scheduler event queue) expires (in other words, is automatically purged from the queue). If NULL, Scheduler-generated events expire after 24 hours.

value

The new value of the attribute

Usage Notes

To run SET_SCHEDULER_ATTRIBUTE, you must have the MANAGE SCHEDULER privilege.

STOP_JOB Procedure

This procedure stops currently running jobs or all jobs in a job class. Any instance of the job will be stopped. After stopping the job, the state of a one-time job will be set to STOPPED whereas the state of a repeating job will be set to SCHEDULED or COMPLETED depending on whether the next run of the job is scheduled.

If a job pointing to a chain is stopped, all steps of the running chain that are running will be stopped.

Syntax

DBMS_SCHEDULER.STOP_JOB (
   job_name         IN VARCHAR2
   force            IN BOOLEAN DEFAULT FALSE);

Parameters

Table 93-62 STOP_JOB Procedure Parameters

Parameter Description

job_name

The name of the job or job class. Can be a comma-delimited list. For a job class, the SYS schema should be specified.

If the name of a job class is specified, the jobs that belong to that job class are stopped. The job class is not affected by this call.

force

If force is set to FALSE, the Scheduler tries to gracefully stop the job using an interrupt mechanism. This method gives control back to the slave process, which can update the status of the job in the job queue to stopped. If this fails, an error is returned.

If force is set to TRUE, the Scheduler will immediately terminate the job slave. Oracle recommends that STOP_JOB with force set to TRUE be used only after a STOP_JOB with force set to FALSE has failed.

Use of the force option requires the MANAGE SCHEDULER system privilege.

Usage Notes

STOP_JOB without the force option requires that you be the owner of the job or have ALTER privileges on that job. You can also stop a job if you have the CREATE ANY JOB or MANAGE SCHEDULER privilege.

STOP_JOB with the force option requires that you have the MANAGE SCHEDULER privilege.