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

If you want to keep the row with the lowest id value:

 DELETE n1 FROM 'yourTableName' n1, 'yourTableName' n2 WHERE n1.id > n2.id AND n1.email = n2.email

If you want to keep the row with the highest id value:

 DELETE n1 FROM 'yourTableName' n1, 'yourTableName' n2 WHERE n1.id < n2.id AND n1.email = n2.email