primary key

[jisuprusty]

hi ,
help me
How is it possible to create a primary key if already a primary key is present in a table ?

[prohan]

Does the table have any data in it?

If not, you could simply drop it, recreate it and then create the correct Primary key constraint.
But you have to be careful of Foreign key references in tables that are children of this one.

[debasisdas]

There can be only one Primary key in a table.

[amitpatel66]

hi ,
help me
How is it possible to create a primary key if already a primary key is present in a table ?

There can be only one primary key on the table. Either with single column or multi column (composite key)

So you need to drop the existing one and create a new one. Remember if you create a new one as composite key and any column has a duplicate or null value then you will not be able to create the primary key.