First page Back Continue Last page Graphics

Hash Join Parameters

HASH_JOIN_ENABLED
- Database and Session level
- Dynamic
- TRUE allows hash joins
PGA_AGGREGATE_TARGET
- Session level only
- Dynamic
- Total aggregate size for all PGA’s
- Deprecates HASH_AREA_SIZE

Notes:

Hash joins require the use of some initialization parameters:
HASH_JOIN_ENABLED - This will allow Oracle to consider hash joins. If set to False, Oracle will not utilize hash joins.
PGA_AGGREGATE_TARGET – The total amount of PGA space for a processes. This parameter deprecates HASH_AREA_SIZE (the maximum amount of PGA memory, in bytes, to be used by the session for the hash join). PGA_AGGREGATE_TARGET is used when WORKAREA_SIZE_POLICY is set to AUTO, otherwise the HASH_AREA_SIZE parameter value is used.