前几天做一个需求用到了sql in 子查询，
大概sql如下
SELECT * FROM table_a WHERE id IN (SELECT id FROM table_id_list)
执行时间150m，完全没法忍受
单独执行
SELECT id FROM table_id_list
秒查，只有七八行结果。
把查询结果写死在sql中
SELECT * FROM table_a WHERE id IN (1,2,3,4,5)
依然秒查
解决方案
再把ID列表select一次
SELECT * FROM table_a WHERE id IN (SELECT id from(SELECT id FROM table继续阅读 »
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