How to remove unique key from mysql table

I need to remove a unique key from my mysql table. How can remove that using mysql query.

I tried this but it is not working

alter table tbl_quiz_attempt_master drop unique key;

Please help me

Thanks

All keys are named, you should use something like this -

ALTER TABLE tbl_quiz_attempt_master
  DROP INDEX index_name;

To drop primary key use this one -

ALTER TABLE tbl_quiz_attempt_master
  DROP INDEX `PRIMARY`;

ALTER TABLE Syntax.