How to delete duplicates on a MySQL table?

Question

I need to DELETE duplicated rows for specified sid on a MySQL table.

How can I do this with an SQL query?

Answer 1

This here will make the column column_name into a primary key, and in the meantime ignore all errors. So it will delete the rows with a duplicate value for column_name.

ALTER IGNORE TABLE `table_name` ADD PRIMARY KEY (`column_name`);