Drop a single key out of a composite?

[Hartmann]

I have a composite primary key made up of 2 foreign keys and a primary key. I need to drop the single primary key (in this case "page_num") but I cannot figure out how to do it and there's no documentation at mysql.com.

Any ideas?

[lilleman]

Hi,

Perhaps this could be what you're looking for?

ALTER TABLE tbl_name DROP PRIMARY KEY,
  ADD PRIMARY KEY (first_field, second_field);

[Hartmann]

Nope. I get an error as it's trying to "rename tables"...

[lilleman]

Hi,

I just tried the query on a simple test table, and it worked for me...

[Hartmann]

It didn't work but I figured out a way to do it... The foreign keys were keeping it from being dropped.