在mysql中提供了ltrim,rtrim函数来删除字符的首毛空格那么如果我要删除字符如\"abc fdsa\"应该如何做来,下面我们来看教程
ltrim 函数
代码如下 | 复制代码 |
> concat('.', ltrim(' ddd '), '.'); |
rtrim函数
代码如下 | 复制代码 |
mysql> select concat('.', rtrim(' ddd '), '.'); |
trim 字符串函数,实在是强大。它不仅能消除字符串首尾部的空格,还可以消除我们指定的任意字符。ltrim(), rtrim() 只是它的一个功能子集。
代码如下 | 复制代码 |
UPDATE `tran` SET `status` = '1' WHERE trim( replace( `msg`, 'rn', ' ' ) ) = '我爱你'; |
数据中的回车换行等替换成空格之后再trim掉,就达到目的了,虽然不是特别完美,但是由于没办法在用户录入的时候控制,所以只能出此下策,好在MySQL内置函数的效率还是很有保证的

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