阅读背景:

MySQL中对于not in和minus使用的优化

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!--NEWSZW_HZH_BEGIN--

优化前:

select count(t.id)
 from test t
 where t.status = 1
  and t.id not in (select distinct a.app_id
           from test2 a
           where a.type = 1
            and a.rule_id in (152, 153, 154))
      
 17:20:57 laojiu>@plan

PLAN_TABLE_OUTPUT
————————————————————————————————————————-
Plan hash value: 684502086

—————————————————————————————-
| Id | Operation      | Name       | Rows | Bytes | Cost (%CPU)| Time   |
—————————————————————————————-
|  0 | SELECT STATEMENT  |         |   1 |  18 |  176K (2)| 00:35:23 |
|  1 | SORT AGGREGATE   |         |   1 |  18 |      |     |
|* 2 |  FILTER      |         |    |    |      |     |
|* 3 |  TABLE ACCESS FULL| test   | 1141 | 20538 |  845  (2)| 00:00:11 |
|* 4 |  TABLE ACCESS FULL| test2 |   1 |  12 |  309  (2)| 00:00:04 |
—————————————————————————————-

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

  2 
select count(t.id)
 f




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