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mysql enum类型字段_MySQL

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Jun 01, 2016 pm 01:07 PM

ENUM是一个字符串对象，其值来自表创建时在列规定中显式枚举的一列值

每个数值都对应一个索引值，并且是按照创建字段时候规定的顺序，例如enum（'a','b','c'）,对应索引值为（1,2,3）,null和''为保留值，只有当插入的值不再该范围内，就用数值0取代，可以用该方法来筛选是否非正常插入的数据 where column=0

在查询的时候要注意，特别是数值enum('0','1','2')对应索引值（1,2,3）,where column=1，并不能查询出来该字段为1的数据，出来的结果会是列值为0的数据

只能写成where column='1',才是正确列值等于1的数据

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