第一篇文章，做一个测试

来源：互联网发布：聊天中vb是什么意思编辑：程序博客网时间：2024/05/17 03:06
写一个SQL语句：
SQL> select  2   /*+ qb_name(outer) leading(t2@inner) use_nl(t1@outer) */ *  3    from t1  4   where object_id in (select /*+ qb_name(inner) */  5                        object_id  6                         from t2);已选择100000行。执行计划----------------------------------------------------------Plan hash value: 653523239---------------------------------------------------------------------------------------| Id  | Operation                    | Name   | Rows  | Bytes | Cost (%CPU)| Time     |---------------------------------------------------------------------------------------|   0 | SELECT STATEMENT             |        |   112K|    23M| 57268   (1)| 00:11:28 ||   1 |  NESTED LOOPS                |        |       |       |            |          ||   2 |   NESTED LOOPS               |        |   112K|    23M| 57268   (1)| 00:11:28 ||   3 |    SORT UNIQUE               |        |   112K|  1431K|   320   (1)| 00:00:04 ||   4 |     TABLE ACCESS FULL        | T2     |   112K|  1431K|   320   (1)| 00:00:04 ||*  5 |    INDEX UNIQUE SCAN         | IDX_T1 |     1 |       |     0   (0)| 00:00:01 ||   6 |   TABLE ACCESS BY INDEX ROWID| T1     |     1 |   207 |     1   (0)| 00:00:01 |---------------------------------------------------------------------------------------Predicate Information (identified by operation id):---------------------------------------------------   5 - access("OBJECT_ID"="OBJECT_ID")Note-----   - dynamic sampling used for this statement (level=2)统计信息----------------------------------------------------------          0  recursive calls          0  db block gets     109722  consistent gets       1416  physical reads          0  redo size    5171130  bytes sent via SQL*Net to client      73845  bytes received via SQL*Net from client       6668  SQL*Net roundtrips to/from client          1  sorts (memory)          0  sorts (disk)     100000  rows processed
0 0