Re: primary key and uniqueness

--Boundary_(ID_VZAyTmEAzstZRjxlJFEPjQ) Content-type: text/plain; charset=us-ascii Content-disposition: inline Content-transfer-encoding: 7BIT Martin A PK *will* be unique, so declaring a PK will do it. The only problem in declaring PK with a CREATE TABLE or ALTER TABLE is that Informix generates the underlying unique index for you and this has a system defined name. The name is such that you cant use a DROP INDEX to drop this index - the only way to get rid of it would be drop the PK. So what I usually did for such cases was to create the unique index first, then create the PK for documentation purposes. Just my $ 0.02 Sujit "Martin A. Marques" <martin@math.unl.edu.ar> on 06/24/2000 05:32:24 AM To: Obnoxio The Clown <obnoxio@hotmail.com>, martin@math.unl.edu.ar, informix-list@iiug.org cc: Subject: Re: primary key and uniqueness --Boundary_(ID_VZAyTmEAzstZRjxlJFEPjQ) Content-type: text/plain; charset=iso-8859-1 Content-disposition: inline Content-transfer-encoding: quoted-printable On Sat, 24 Jun 2000, Obnoxio The Clown wrote: > From: "Martin A. Marques" <martin@math.unl.edu.ar> > >So with PRIMARY KEY I get it all! Do I get some other constraint? > > In what way? I mean, if the colum is declared as a PRIMARY KEY, then it will be UNIQ= UE too? > >One last one. Is it posible to reference a field on a table to a fie= ld on > >another table that is not a PRIMARY KEY? > > No. Not using declarative syntax, anyway. What do you mean with declarative syntax? If you respond RTFM, at least= tell me what FM. ;-) Thanks, and I got the tables created just as I wanted. :-) -- "And I'm happy, because you make me feel good, about me." - Melvin Udal= l ----------------------------------------------------------------- Mart=EDn Marqu=E9s email: martin@math.unl.edu.ar Santa Fe - Argentina http://math.unl.edu.ar/~martin/ Administrador de sistemas en math.unl.edu.ar ----------------------------------------------------------------- = --Boundary_(ID_VZAyTmEAzstZRjxlJFEPjQ)--