小弟我想查找同一字段内 某几个特定的值 如何优化
我想查找同一字段内 某几个特定的值 怎么优化。
SELECT * FROM `tab` WHERE a3=1 or a3=2 or a3=3 or a3=4 or a3=5..........a3=29 a3=30
查找a3内值为1到30的。怎么优化的更简洁。高效一点
------解决方案--------------------
a3 in(1,2,3)
------解决方案--------------------
SELECT * FROM `tab` WHERE a3 between 1 and 30 ;
这样试试。或者 in(1,2..................)
------解决方案--------------------
楼上2种都好，过于10个还是用between 好些吧..
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