QUERY_REWRITE_ENABLED

QUERY_REWRITE_ENABLED allows you 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.