News for hackers. Stuff that matters.

A comment on Joins 13 Ways. Parent comment

Re:Joins 13 Ways by jimwhite42 on Sunday July 09, 2023 @11:38AM (#36655362)
True, but I think slightly pedantic for this context. I think there have been proposed relational operators which produce the result you describe - a join, then remove the join key fields from the result.

If we are in a pedantic mood, also, a relational-tuple is not exactly the same as a mathematical tuple, relational tuples take different forms depending on who's system you are following (e.g. whether the fields are ordered or not).

[ Parent | on HN ]
Re:Joins 13 Ways by keithalewis on Saturday July 15, 2023 @11:49PM (#36743409)
Just endeavoring to make true statements. A relation on sets A and B is a subset R of the Cartesian product of A and B. E. F. Codd had something else in mind with his definition of join. Do you think he got that wrong?
[ Parent | on HN ]