Re: Lucid statement of the MV vs RM position?

Hi Ralph,

I just don't understand how you could read my little article and think I got those two points wrong.

I didn't say the RM was based on tables. I said 'The method used is formal, mathematical, and uses data which is in a tabular form.' When the basic concept is rows and columns, I think that's a fair statement.  Maybe I was wrong to say "The tabular form was inspired by data storage structures where data was held in tables of fixed length fields." However, if Codd did or did not draw inspiration from the source I thought he had - so what?

I also didn't say that the RM said anything about how the data was stored - I said this

"...we now have three levels. They are

• The presentation layer
• The logical layer
• The storage layer

The logical layer is the core part of the Relational Model."

This seems to be exactly what you are saying!

Are you rebutting some other thing you read, or do you not read properly, or what?

I don't think the CS degree results have anything to do with what Oracle or IBM or Microsoft do for their design decisions. I just don't follow your logic on this one.

Does any DBMS optimise dynamically correctly? My Systems Analysis days are long past, but it seems to me this would be one of those really complex problems that can never be solved.

Your statement "A good DBMS should allow the DBA to suggest optimizations..." seems more than a little anthropomorphic, don't you think? Received on Mon Apr 24 2006 - 02:37:03 CEST