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This finding can only appear after running the "Get Best Plan" command in the Bind Variables tab.
It indicates that some bind values may lead Oracle to choose a different execution plan than others. This does not mean that when those bind values are used for the statement that their relevant plan will be used. This depends on which version of Oracle is being used, whether the statement’s plan exists in memory, and whether the init.ora parameter "_optim_peek_user_binds" is set to TRUE or FALSE.
| Preferable Plan Detected by Oracle |
| Description | |
| What to do next | Perform one of the following options: n Check the PLAN_HASH_VALUE field that appears in the left pane in the Bind Variables tab and examine the difference between plans of different bind sets. n Consider running the statement using a different bind set leading to a different plan, and compare their run time. |
| Advice | If different execution plans result in a fluctuation in run time consider the following: n Fixing an optimal plan using outlines or profiles. n Disabling bind peeking by setting the "_optim_peek_user_binds" parameter to FALSE n Consider using literals instead of bind variables. Note: Notice that setting "_optim_peek_user_binds" to FALSE will influence all statements running in the selected instance. |
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