How to remove duplicate entries from a mysql db?

This command adds a unique key, and drops all rows that generate errors (due to the unique key). This removes duplicates.

ALTER IGNORE TABLE table ADD UNIQUE KEY idx1(title); 

Edit: Note that this command may not work for InnoDB tables for some versions of MySQL. See this post for a workaround. (Thanks to “an anonymous user” for this information.)

Leave a Comment