Path: utzoo!attcan!uunet!cimshop!davidm From: cimshop!davidm@uunet.UU.NET (David S. Masterson) Newsgroups: comp.databases Subject: Re: Join Contest Message-ID: Date: 17 Jul 90 17:12:04 GMT References: <5265@plains.UUCP> <933@dgis.dtic.dla.mil> Sender: davidm@cimshop.UUCP Organization: Consilium Inc., Mountain View, California. Lines: 22 In-reply-to: jkrueger@dgis.dtic.dla.mil's message of 16 Jul 90 23:31:09 GMT In article <933@dgis.dtic.dla.mil> jkrueger@dgis.dtic.dla.mil (Jon) writes: gus@plains.NoDak.edu writes: >Recently I heard that an IBM-type db person claimed that it's >not uncommon in commercial db applications to join as many as >10-15 (maybe even 30) tables in a single query. It is uncommon. Ask your IBM-type db person to substantiate his claim. "Extraordinary claims require extraordinary justification". In fact it's difficult to design a query that makes sense with more than about five joins. Try it. Already been tried. Try to do a parts explosion problem (of any sort) without the recursive join operator that Codd speaks of. Tain't nothing extraordinary about it. -- =================================================================== David Masterson Consilium, Inc. uunet!cimshop!davidm Mt. View, CA 94043 =================================================================== "If someone thinks they know what I said, then I didn't say it!"