Re: Select In From Clause

David Williams <djw@smooth1.demon.co.uk> wrote: :In article <5opfk1$cn4@cssun.mathcs.emory.edu>, Jonathan Leffler :<johnl@informix.com> writes :>>From: Jeremy Rickard <Jeremy@jbdr.demon.co.uk> :>>Date: Tue, 24 Jun 1997 19:28:34 +0100 :>>X-Informix-List-Id: <news.39612> :>> :>>Chez David <dmitchell@SagentTech.com> writes: :>> :>>>Anyone know if Informix ( 7.x ) supports SQL of this form? SQL Server and :>>>Oracle seem to. :>>> :>>>SELECT :>>>T0.C0, T1.C0 :>>>FROM :>>>( SELECT JOB_ID AS C0 FROM JOBS ) T0, :>>>( SELECT JOB_ID AS C0 FROM EMPLOYEE ) T1 :>>>WHERE :>>>T0.C0 = T1.C0 :> :> :>Well, I don't know about the general opinion, but I'm in favour of it. :> : Nice idea but a little too complex for me to be happy with. I'd hate : to try and debug something like this with several : ...col1 as col2... and ,,,tab1) tab2 : clauses in it.. : : I could imagine some truely horrendous queries could be created with : it... True, but this and most of the other new facilities of SQL 92 and the new SQL 3 are an absolute requirement for us within a not too distant future. There are so many things that are hard and in some cases impossible to do in SQL that would be simple with all the new options. SQL allways had the problem one could create horrendous queries. I agree that is a problem, but the problem with not beeing able to do the query at all (having to resort to fairly heavy programming in some other language instead) isn't better. SQL 92 has a lot of other niceties like the case construct ++ and SQL 3 is another world altogether. Prepare yourself for relearning what a relational database can do and how to design the databases. It will be very nice. : :>Yours, :>Jonathan Leffler (johnl@informix.com) #include <disclaimer.h> : :-- :David Williams Nils.Myklebust@idg.no NM Data AS, P.O.Box 9090 Gronland, N-0133 Oslo, Norway My opinions are those of my company The Informix FAQ is at http://www.iiug.org