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0 pointsgregjor2y ago0 comments

> there’s nothing in [Codd’s] principles that require tables/rows of tuples.

Have you read Codd’s Rules #1 and #2? Pretty clear on this point.

https://en.wikipedia.org/wiki/Codd%27s_12_rules

Technically the relational model uses the term relation to refer to an unordered set of tuples, where every tuple has a key (one or more elements) to uniquely identify it, and every tuple has the same number of items, of the same type. Tables are relations. So are the results of a query, which can include joins.

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ghusbands2y ago

> > there’s nothing in [Codd’s] principles that require tables/rows of tuples.

You're misquoting; is that intentional? The post you're replying to says the principles that inspired/predate Codd don't require tables/tuples. Thus, the details of Codd's relational model are irrelevant.

gregjorOP2y ago

If I misunderstood the principles you refer to I apologize. Codd's relational rules and designs for relational databases developed from relational algebra theory, which was introduced by... Edgar F. Codd.

https://en.m.wikipedia.org/wiki/Relational_algebra

If you meant to refer to some other principles can you name them or give a link or something?

bazoom422y ago

What principles are you talking about then?

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