Re: pro- foreign key propaganda?
Date: Tue, 20 May 2008 15:56:09 GMT
David Cressey wrote:
> Absolutely. In the previous comments in this thread, the term "candidate
> key" was used.
> You can shorten that to simply, "key", if you like. No problem. ...
In the 1970 mainframe culture that Codd was trapped in, 'key' had an extremely physical connotation, in fact some hardware supported 'keys' directly with dedicated machine-level operators. Many practitioners had grown up depending on file-level keys, as for IMS, its various keys were all encumbered with various navigational meanings. I think Codd was just as much a pragmatist as a theorist and even though his keys weren't at all the same thing he might have used continued the term to ease his 'sales pitch'. If he had called them, say, the 'inference set', he might have expected even more resistance than he did from the ignorants of the day. While academics embraced his ideas quickly, he suffered many personal attacks from the powerful marketeers at a time when IBM was maybe more dominant than microsoft is today. Ironic, because IMS was used as way to help sell then big IO-oriented slow-cpu iron and the implementations that followed Codd were attacked for supposedly needing more hardware than IMS did. I remember an Amdahl salesman saying, "give me more of this relational stuff, I'll sell more cpu's!". Received on Tue May 20 2008 - 17:56:09 CEST