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If you are wondering which execution plan the query is using when you run a query, you must run the command “set autotrace on explain” before running the query.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 | SQL> set autotrace on explain; SQL> select sysdate from dual; SYSDATE --------- 26-SEP-11 Execution Plan ---------------------------------------------------------- Plan hash value: 1546270724 ----------------------------------------------------------------- | Id | Operation | Name | Rows | Cost (%CPU)| Time | ----------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | 2 (0)| 00:00:01 | | 1 | FAST DUAL | | 1 | 2 (0)| 00:00:01 | ----------------------------------------------------------------- |
