| SQL> select table_name,index_name,column_name,column_position from user_Ind_columns where table_name='EMPLOYEES'; TABLE_NAME INDEX_NAME COLUMN_NAME COLUMN_POSITION -------------------- ------------------------------ --------------- --------------- EMPLOYEES EMP_EMAIL_UK EMAIL 1 EMPLOYEES EMP_EMP_ID_PK EMPLOYEE_ID 1 EMPLOYEES EMP_DEPARTMENT_IX DEPARTMENT_ID 1 EMPLOYEES EMP_JOB_IX JOB_ID 1 EMPLOYEES EMP_MANAGER_IX MANAGER_ID 1 EMPLOYEES EMP_NAME_IX LAST_NAME 1 EMPLOYEES EMP_NAME_IX FIRST_NAME 2 SQL> set autot traceonly explain SQL> select last_name,first_name from employees; Execution Plan ---------------------------------------------------------- Plan hash value: 2228653197 -------------------------------------------------------------------------------- | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | -------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 107 | 1605 | 1 (0)| 00:00:01 | | 1 | INDEX FULL SCAN | EMP_NAME_IX | 107 | 1605 | 1 (0)| 00:00:01 | -------------------------------------------------------------------------------- |
来自 “ ITPUB博客 ” ，链接：https://blog.itpub.net/10972173/viewspace-539702/ ，如需转载，请注明出处，否则将追究法律责任。
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