operations that can be parallelized
You can use parallel execution for any of the following:
- Access methods : Some examples are table scans, index fast full scans, and partitioned index range scans. Hint: PARALLEL and PARALLEL_INDEX
- Join methods : Some examples are nested loop, sort merge, hash, and star transformation.
- DDL statements : Some examples are CREATE TABLE AS SELECT, CREATE INDEX, REBUILD INDEX, REBUILD INDEX PARTITION, and MOVE/SPLIT/COALESCE PARTITION
- DML statements : Some examples are INSERT AS SELECT, updates, deletes, and MERGE operations. It require ALTER SESSION ENABLE PARALLEL DML;
- Parallel query: You can parallelize queries and subqueries in SELECT statements, plus the query portions of DDL statements and DML statements (INSERT, UPDATE, DELETE, and MERGE).
- Miscellaneous SQL operations : Some examples are GROUP BY, NOT IN, SELECT DISTINCT, UNION, UNION ALL, CUBE, and ROLLUP, plus aggregate and table functions.
- Tools: SQL*Loader and expdp & impdp tools , external tables etc . An important point to remember is that indexes are not maintained during a parallel load.
- parallel recovery and rman backup
- Others: parallel transfer archived logs to dataguard during GAP using “MAX_CONNECTIONS”
ref: http://zhaolinjnu.blog.sohu.com/66719987.html
欢迎补充。


















