查找mysql字段中固定字符串并替换的几个方法

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查找mysql字段中固定字符串并替换的几个方法_php技巧

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May 17, 2016 am 09:09 AM

replace

我们的要求是，把地址字段的中国去掉，并跟据地址字段来设置所属省份的(province_id) 字段。

第一、替找字符串，我们可以用mysql里的replace 这个用法，本博也有提到。详见：http://www.jb51.net/article/31374.htm

好我们把 "中国" 这个字符给去掉。

update table set address = replace(address ,'中国','')

第二、要根据地址字段的开头字符并更新province_id字段、SQL语句如下

UPDATE table SET province_id=11 where LEFT(address,2)='福建'

这里用到的是mysql的LEFT函数,查找地址字符的前两个字符，判断是否为'福建' 如果是,sql就会更新province_id字段为11。这里的11是省份表福建所对应的ID.

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