Miscellaneous hints
The following hints cover other types of optimization choices:
- APPEND
Enables direct-path INSERTs if you are running in serial mode (i.e., you are not running Enterprise Edition).
- NOAPPEND
Disables direct-path INSERTs for the statement.
- CACHE( table )
Places table in the buffer cache at the most recently used end of the least recently used (LRU) list when a full table scan is performed, as for a small lookup table.
- NOCACHE
Places table in the buffer cache at the least recently used end of the LRU list when a full table scan is performed. With Oracle9i Release 2, small tables are automatically cached.
- UNNEST
Specifies that a subquery is merged with the parent query. This hint is new with Oracle9i.
- NO_UNNEST
Turns off UNNEST for specific query blocks. This hint is new with Oracle9i.
- PUSH_PRED( table )
Pushes a join predicate into a view. This hint was called PUSH_JOIN_PRED in Oracle8.
- NO_PUSH_PRED( table )
Prevents pushing a join predicate into a view. This hint was called NO_PUSH_JOIN_PRED in Oracle8.
- PUSH_SUBQ
Forces nonmerged subqueries to be evaluated at the earliest possible step in the optimization process. Appropriate if the subquery is inexpensive and limits the number of rows evaluated.
- NO_PUSH_SUBQ
Forces nonmerged subqueries to be evaluated at the earliest possible step in the optimization process. New with Oracle9i.
- ORDERED_PREDICATES
Forces optimizer to preserve the order of the predicates in the WHERE clause. This hint is specified in the WHERE clause. New ...