Update all lowercase column values

Question

Suppose I have something like this

uid tag 1 HeLLo 2 heLLO 3 HELLO 4 hello 

How to update all the values ​​in the tag column to:

 uid tag 1 hello 2 hello 3 hello 4 hello 

using MySQL?

Answer 1

See http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_lower

 UPDATE table_name SET tag = LOWER(tag) 

Answer 2

LOWER ()

 update table set tag = LOWER(tag) 

Answer 3

Case insensitive version and inclusion of the WHERE clause if you do not want to update the entire column:

 UPDATE table SET tag = LOWER(tag) WHERE LOWER(tag) != tag COLLATE Latin1_General_CS_AS 

The COLLATE string will make it work if your database uses case insensitivity like mine.