Re: Implementation of boolean types.

>> Where do you think the definition of natual join comes from? <<

Getting serious for a minute, Tom Johnston had a paper and a conversation with Dr. Codd about problems with the Natural Join because we cannot be sure which of the two or more columns are or are not in the resulting relation.

>> A language not having a clean treatment of the boolean type in version 1 is a sign of bad design. <<

Procedural languages, not declarative ones. Dijkstra "only" worked with non-deterministic procedural languages. I think that we grew up with the Dijkstra/ Manna/ Gries model of programming that we had a bitch of a time with RM. I think I can say that with authority since my first Master's Thesis was on an algebra of Structured Programming :) Received on Fri Jul 15 2005 - 02:46:56 CEST