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发布时间:2014-01-03 16:28:15
关于IN和OR的区别,在High performance mysql 3rd中,有一段话描述的非常清楚:IN() list comparisonsIn many database servers, IN() is just a synonym for multiple OR clauses, because the two are logically equivalent. Not so in MySQL, which sorts the values in theIN() list and uses a fast binary s.........【阅读全文】