Need for PK in Subtables?
From: Rob Williamson <robw_at_physics.umd.edu>
Date: Thu, 25 Jul 2002 11:15:09 -0400
Message-ID: <3D4015FD.492496F7_at_physics.umd.edu>
Date: Thu, 25 Jul 2002 11:15:09 -0400
Message-ID: <3D4015FD.492496F7_at_physics.umd.edu>
I have a Personnel table and a Salaried_Employee table:
Personnel ( ID (PK),Name, etc)
Salaried_Emp( ID (PK)(FK),Salary, etc )
My question: Is the Primary Key for Salaried_Emp ( the sub-table )
redundant?
Is there any real reason to have the second primary key and just have ID
the foreign key to Personnel.ID? It seems like the data integrity would
be taken care of by the
Personnel.ID PK?
Any body got any thoughts on this.
Rob Received on Thu Jul 25 2002 - 17:15:09 CEST