1.239 OPTIMIZER_SECURE_VIEW_MERGING

OPTIMIZER_SECURE_VIEW_MERGING enables the optimizer to use view merging to improve query performance without performing the checks that would otherwise be performed to ensure that view merging does not violate any security intentions of the view creator.

Property Description

Parameter type

Boolean

Default value

true

Modifiable

ALTER SYSTEM

Modifiable in a PDB

Yes

Range of values

true | false

Basic

No

Oracle RAC

Multiple instances can have different values

Values

  • false

    Oracle Database does not perform security checks that may prevent view merging and predicate move-around.

  • true

    Oracle Database performs checks to ensure that view merging and predicate move-around do not violate any security intentions of the view creator.

To enable the optimizer to use view merging for any query issued by a user, you must grant the MERGE ANY VIEW privilege to the user. Grant the MERGE VIEW privilege to a user on specific views to enable the optimizer to use view merging for queries on these views. These privileges are required only under specific conditions, such as when a view is not merged because the security checks fail.

See Also:

Oracle Database SQL Tuning Guide for more information about view merging