如何在MySQL中检查大写字母? [英] How to check for uppercase letters in MySQL?

问题描述

我想检查字符串是否仅包含大写字母.我知道RLIKE/REGEXP在MySQL中不区分大小写.所以我尝试使用:upper:字符类:

I want to check, if a string consits only of uppercase letters. I know that RLIKE/REGEXP are not case sensitive in MySQL. So I tried to use the :upper: character class:

SELECT 'z' REGEXP '^[[:upper:]]+$';

这是正确的，尽管z是小写，...为什么?

This gives true, although the z is in lower case,... why?

推荐答案

REGEXP不区分大小写，除非与二进制字符串一起使用.

REGEXP is not case sensitive, except when used with binary strings.

http://dev.mysql.com/doc/refman/5.7/en/regexp.html

因此请记住，只需执行以下操作:

So with that in mind, just do something like this:

SELECT * FROM `users` WHERE `email` REGEXP BINARY '[A-Z]';

使用上面的示例，您将获得包含一个或多个大写字母的电子邮件列表.

Using the above example, you'd get a list of emails that contain one or more uppercase letters.

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