You can configure the comparison method that determines when a SQL Performance Analyzer task performs line-by-line comparison of execution plans. By default, a SQL Performance Analyzer task performs line-by-line comparison of execution plans only if the plan hash value is unknown.
To configure the execution plan comparison method of an analysis task:
Use the SET_ANALYSIS_TASK_PARAMETER procedure to set the value of the PLAN_LINES_COMPARISON parameter.
Table 3-1 lists the valid values for the PLAN_LINES_COMPARISON parameter.
Table 3-1 SQL Performance Analyzer Task Execution Plan Methods
| Method | Description |
|---|---|
|
|
The analysis task always performs a line-by-line comparison of execution plans. |
|
|
The analysis task performs a line-by-line comparison of execution plans only if the computation of the plan hash value for the first SQL trial has changed or the second SQL trial is unavailable. |
|
|
The analysis task performs a line-by-line comparison of execution plans only if the plan hash value is unknown. This is the default value. |
The following example shows how to set the execution plan method for an analysis task to AUTO:
EXEC DBMS_SQLPA.SET_ANALYSIS_TASK_PARAMETER(task_name => 'my_spa_task', -
parameter => 'PLAN_LINES_COMPARISON', -
value => 'AUTO');
Oracle Database PL/SQL Packages and Types Reference for information about the DBMS_SQLPA.SET_ANALYSIS_TASK_PARAMETER procedure