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Mysqlselect语句设置默认值_MySQL
- WBOYOriginal
- 2016-06-01 13:13:321329browse
1.在没有设置默认值的情况下：
SELECT userinfo.id, user_name, role, adm_regionid, region_name , create_timeFROM userinfoLEFT JOIN region ON userinfo.adm_regionid = region.id结果：
设置显示默认值：
SELECT userinfo.id, user_name, role, adm_regionid, IFNULL(region_name,0) as region_name, create_timeFROM userinfoLEFT JOIN region ON userinfo.adm_regionid = region.id即：如果region_name一列的值为空，则显示为0，结果为：
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