QUERY_REWRITE_ENABLED

Property	Description
Parameter type	String
Syntax	`QUERY_REWRITE_ENABLED = { false \| true \| force }`
Default value	If `OPTIMIZER_FEATURES_ENABLE` is set to `10.0.0` or higher, then `true` If `OPTIMIZER_FEATURES_ENABLE` is set to `9.2.0` or lower, then `false`
Modifiable	`ALTER SESSION`, `ALTER SYSTEM`
Basic	No
Oracle RAC	Multiple instances can have different values.

Use QUERY_REWRITE_ENABLED to enable or disable query rewriting globally for the database.

Values

false

Oracle does not use rewrite.
true

Oracle costs the query with rewrite and without rewrite and chooses the method with the lower cost.
force

Oracle always uses rewrite and does not evaluate the cost before doing so. Use force when you know that the query will always benefit from rewrite and when reduction in compile time is important.

To take advantage of query rewrite for a particular materialized view, you must enable query rewrite for that materialized view, and you must enable cost-based optimization.