SQL执行异常系列之——统计信息不准

SQL> explain plan for select a.object_name,b.object_id
from static_test a,static_test1 b
where a.object_id=b.object_id; 2 3

Explained.

SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT
-------------------------------------------------------------------------------------------------
Plan hash value: 1637592733

------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 35 | 344 (0)| 00:00:05 |
| 1 | NESTED LOOPS | | 1 | 35 | 344 (0)| 00:00:05 |
| 2 | NESTED LOOPS | | 1 | 35 | 344 (0)| 00:00:05 |
| 3 | TABLE ACCESS FULL | STATIC_TEST1 | 1 | 5 | 343 (0)| 00:00:05 |
|* 4 | INDEX RANGE SCAN | STATIC_TEST_IDX | 1 | | 1 (0)| 00:00:01 |
| 5 | TABLE ACCESS BY INDEX ROWID| STATIC_TEST | 1 | 30 | 1 (0)| 00:00:01 |
------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

4 - access("A"."OBJECT_ID"="B"."OBJECT_ID")

17 rows selected.

SQL执行异常系列之——统计信息不准

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