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exists() 语句 条件放在外面提速不少
select * from T_ZDJZD a where exists(select * from T_ZDJZX b where a.ZD_ID=b.ZD_ID and ZD_ID=73090 and a.JZD_ID=b.QS_JZD and a.JZ_XH<>b.JZ_XH)
优化为:
select * from T_ZDJZD a where exists(select * from T_ZDJZX b where a.ZD_ID=b.ZD_ID and a.JZD_ID=b.QS_JZD and a.JZ_XH<>b.JZ_XH) and a.ZD_ID=73090
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