TZ_OFFSET

The TZ_OFFSET function returns the time zone offset corresponding to the argument based on the date the statement is executed.

Note:

Timezone region names are needed by the daylight savings feature. The region names are stored in two time zone files. The default time zone file is a small file containing only the most common time zones to maximize performance. If your time zone is not in the default file, then you do not have daylight savings support until you provide a path to the complete (larger) file by way of the ORA_TZFILE environment variable.

Return Values

A text value in the format shown below which represents the offset

'{ + | - } hh : mi'

Syntax

TZ_OFFSET( 'time_zone_name' | '{ + | - } hh : mi' | SESSIONTIMEZONE | DBTMEZONE)

Parameters

time_zone_name: A text value that specifies a valid time zone name. For a listing of valid values for time_zone_name, query the TZNAME column of the V$TIMEZONE_NAMES dynamic performance view.

Note:
Timezone region names are needed by the daylight savings feature. The region names are stored in two time zone files. The default time zone file is a small file containing only the most common time zones to maximize performance. If your time zone is not in the default file, then you do not have daylight savings support until you provide a path to the complete (larger) file by way of the ORA_TZFILE environment variable.
{ + | - } hh : mi': Specifies a time zone offset from UTC (which simply returns itself)
SESSIONTIMEZONE: Specifies the time zone of the current session.
DBTIMEZONE: Specifies the value of the Database time zone.