regex - How to check for uppercase letters in MySQL? -

i want check, if string consits of uppercase letters. know rlike/regexp not case sensitive in mysql. tried use :upper: character class:

select 'z' regexp '^[[:upper:]]+$';

this gives true, although z in lower case,... why?

regexp not case sensitive, except when used binary strings.

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

so in mind, this:

select * `users` `email` regexp binary '[a-z]';

using above example, you'd list of emails contain 1 or more uppercase letters.

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