Oracle Scratchpad

June 25, 2009

Explain VIEW

Filed under: Execution plans, Tuning — Jonathan Lewis @ 7:32 pm UTC Jun 25,2009

A brief note on reading execution plans.


------------------------------------------------------------
| Id  | Operation                     | Name    | Time     |
------------------------------------------------------------
|   0 | SELECT STATEMENT              |         | 00:00:17 |
|*  1 |  HASH JOIN                    |         | 00:00:17 |
|   2 |   VIEW                        | VW_SQ_1 | 00:00:01 |
|   3 |    HASH GROUP BY              |         | 00:00:01 |
|   4 |     TABLE ACCESS FULL         | EMP     | 00:00:01 |
|   5 |   VIEW                        |         | 00:00:17 |
|   6 |    TABLE ACCESS BY INDEX ROWID| EMP     | 00:00:17 |
|   7 |     INDEX FULL SCAN           | E_D     | 00:00:01 |
------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   1 - access("DEPT_NO"="OUTER"."DEPT_NO")
       filter("OUTER"."SAL">"VW_COL_1")

(more…)

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