Question

如何优化 oracle <> 利用索引

Answer 1

SQL> set autotrace traceonly explain
SQL> select * from hr.employees where employee_id = 100;

Execution Plan
----------------------------------------------------------
Plan hash value: 1833546154
---------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
---------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 69 | 1 (0)| 00:00:01 |
| 1 | TABLE ACCESS BY INDEX ROWID| EMPLOYEES |