vitaair的博客

mysql中的正则操作 匹配手机号，匹配中文，替换正则匹配hy_user表内tel字段的电话号码：SELECT * FROM hy_user WHERE tel REGEXP "[1][35678][0-9]{9}"SELECT tel FROM hy_user WHERE tel REGEXP "[1][35678][0-9]{9}"SELECT tel FROM hy_user WHERE t...

1.查找表中多余的重复数据，多余的数据是根据单个字段（userId）来判断的SELECT * FROM user WHERE userId IN ( SELECT userId FROM user GROUP BY userId HAVING count(userId) > 1 )2、删除表中多余的重复记录，重复记录是根据单个字段（userId）来判断，只留有rowid最小的记录DELETE...