‎2008 Feb 14 3:08 PM
is it nessary to give primary key in a table.and it should be define only at first position.plzz tell
Edited by: Alvaro Tejada Galindo on Feb 14, 2008 10:10 AM
‎2008 Feb 14 3:11 PM
‎2008 Feb 14 3:12 PM
srinath:
I send you a mail yesterday...Please start using more describing titles or you're going to force me to delete your threads....Table is not a good title...I changed to table and primary key which is better...
Greetings,
Blag.
‎2008 Feb 14 3:15 PM
‎2008 Feb 14 3:17 PM
hi,
s, primary key is mandatory.
it avoid the duplicate of data.for ex (student rollno, material no, employee id)
it should be a unique.
when you create the foreign key table . you want to refer only the primary key field of the reference table(checked table)
when you create the foreign key in the particular table before it should be one primary key.
you can create no of primary keys in one table.
by defaultly the one primary index should be created for that table.
regards
s.surender