Problem in adding Composite primary key

[hirenpatel53]

hello all

i have allready created table and wan to add Composite primary key into that so for that i am using following statement

ALTER TABLE pqrimasterdetail ADD  primary key  (PQRIMasterID,Type,Year,PhysiciansID);

but in not executed successful it gives

the query could not be Executed.
Multiple Primary key Defined

if any one have idea then Please Help asap Thank's in advance

[smantscheff]

Well, if you have defined already a primary key, you cannot have another one. What does show create table pqrimasterdetail say?
You can instead add a second unique key: ALTER TABLE pqrimasterdetail ADD [B]Unique[/B] (PQRIMasterID,Type,YEAR,PhysiciansID);

[hirenpatel53]

thank you for your reply