1.EXPLAIN plan FOR select * ....语句
2.select * from table(dbms_xplan.display);
呈现结果：
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
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| 0 | SELECT STATEMENT | | 1 | 346 | 116 (2)| 00:00:02 |
| 1 | HASH UNIQUE | | 1 | 346 | 116 (2)| 00:00:02 |
| 2 | NESTED LOOPS | | | | | |
| 3 | NESTED LOOPS | | 1 | 346 | 115 (1)| 00:00:02 |
| 4 | NESTED LOOPS OUTER | | 1 | 304 | 114 (1)| 00:00:02 |
|* 5 | HASH JOIN | | 1 | 258 | 113 (1)| 00:00:02 |
| 6 | NESTED LOOPS | | | | | |
| 7 | NESTED LOOPS | | 33 | 7194 | 89 (0)| 00:00:02 |
| 8 | NESTED LOOPS | | 14 | 2072 | 47 (0)| 00:00:01 |
| 9 | INLIST ITERATOR | | | | | |
|* 10 | TABLE ACCESS BY INDEX ROWID| BASE_PERSON_REL_MARKET_AREA | 27 | 2025 | 20 (0)| 00:00:01 |
|* 11 | INDEX RANGE SCAN | MARKET_AREA_SALE_ORG_ID | 35 | | 1 (0)| 00:00:01 |
|* 12 | TABLE ACCESS BY INDEX ROWID | BASE_PERSON | 1 | 73 | 1 (0)| 00:00:01 |
|* 13 | INDEX UNIQUE SCAN | SYS_C0086919 | 1 | | 0 (0)| 00:00:01 |
|* 14 | INDEX RANGE SCAN | IEOP_ROLE_USER_USER_ID | 2 | | 1 (0)| 00:00:01 |
| 15 | TABLE ACCESS BY INDEX ROWID | IEOP_ROLE_USER | 2 | 140 | 3 (0)| 00:00:01 |
|* 16 | TABLE ACCESS FULL | IEOP_ROLE | 19 | 760 | 23 (0)| 00:00:01 |
| 17 | TABLE ACCESS BY INDEX ROWID | CW_BASE_SETTING | 1 | 46 | 1 (0)| 00:00:01 |
|* 18 | INDEX RANGE SCAN | CW_BASE_SETTING_ORG_ID | 1 | | 0 (0)| 00:00:01 |
|* 19 | INDEX UNIQUE SCAN | SYS_C0086771 | 1 | | 0 (0)| 00:00:01 |
|* 20 | TABLE ACCESS BY INDEX ROWID | BASE_CUST_DOC_DEF | 1 | 42 | 1 (0)| 00:00:01 |
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