Re: What is the use of a primary key?

David Cressey wrote:

>>If I can recall correctly DB2 was the first SQL-database system to
>>implement primary keys and that was
>>not until version 1.3, in 1997 - 18 years later! The standard did not
>>have primary keys until
>>SQL-92!! Can hardly blame Codd on that one.
>>
>>
>
>My recollection is that Oracle and DEC Rdb both had primary keys
>declarations in 1994.
>
>My expectation would be that DB2 had primary keys earlier than these two
>products.
>1997 sounds a bit late to me, but I haven't worked with DB2 so I will defer
>to others.
>
OK, OK. So it was only 14 years after Codd's paper...

Come to think of it, I think DB2 had foreign and primary keys starting from V2.0 (and not V1.3).

regards,
Lauri Pietarinen Received on Sun Dec 01 2002 - 21:40:48 CET