Share a primary key column among multiple tables

Question

I have two separate tables to store Admin and other user infoboth the tables have a common column for username and i want the username to be  be unique in both the tables is it possible to have a primary key column across multiple tables?

Vipul Malhotra · Answer

For that when the user enters a username and click on check/submit. At that time you would have to manually check already taken usernames from both the tables. That is the only other resolution that's coming to my mind as of now.

mohan singh · Answer

the solution is fine vipul but i want to ask one thing that the question i asked is possible or not can we do it the way i was doing?

Vipul Malhotra · Answer

Well you certainly need to redesign it in the below manner Table: UserTypes UserTypeId UserTypeText 1 admin 2 other Users Now create another table Table: Users UserId UserTypeID(Foreign key from above table) username FullName 1 1 adminUser Mohan Singh 2 2 user101 Vipul Malhotra This way you need to create username as a Unique key and proceed from there. Hope it helped