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REGEXP
例1.查询字段中包含非英文的数据
SELECT *
FROM `m_user`
WHERE `emp_no`
REGEXP '[^ -~]' =1
列2.这样能把所有不含英文的都搞出来
SELECT *
FROM table
WHERE name
NOT REGEXP '[a-zA-Z0-9]+'
当然除了regexp之外还可以使用FIND_IN_SET,like来操作
FIND_IN_SET
mysql中如何使用FIND_IN_SET(),以及使用FIND_IN_SET()注意的地方,还有F第二世界整理发布IND_IN_SET()与in()的使用区别。
在mysql中查询表字段 pingid = (1,2,3,)
SELECT * FROM `linkinfo` WHERE `pingid` REGEXP '{id},' AND `pingid` NOT REGEXP '[[:alnum:]]+{id},'
使用上面的语句,可以查询出来
Like
MySQL中,SQL的模式缺省是忽略大小写的。下面显示一些例子。注意在你使用SQL模式时,你不能使用=或!=;而使用LIKE或NOT LIKE比较操作符。
SELECT 字段 FROM 表 WHERE 某字段 Like 条件
其中关于条件,SQL提供了四种匹配模式:
1,%:表示任意个或多个字符。可匹配任意类型和长度的字符。
比如
代码如下 复制代码
SELECT * FROM [user] WHERE u_name LIKE ‘%三%'

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