Return-Path: owner-postman Received: from localhost.Berkeley.EDU (localhost.Berkeley.EDU [127.0.0.1]) by nobozo.CS.Berkeley.EDU (8.6.10/8.6.3) with SMTP id UAA18519 for postgres-redist; Sun, 5 Nov 1995 20:17:08 -0800 Resent-From: POSTGRES mailing list Resent-Message-Id: <199511060417.UAA18519@nobozo.CS.Berkeley.EDU> X-Authentication-Warning: nobozo.CS.Berkeley.EDU: Host localhost.Berkeley.EDU didn't use HELO protocol Sender: owner-postman@postgres.Berkeley.EDU X-Return-Path: owner-postman Received: from staff.cs.su.OZ.AU (staff.cs.su.OZ.AU [129.78.8.1]) by nobozo.CS.Berkeley.EDU (8.6.10/8.6.3) with SMTP id UAA17718 for ; Sun, 5 Nov 1995 20:17:05 -0800 Received: from stone.oz.au by staff.cs.su.OZ.AU (mail from daryl for postgres@postgres.berkeley.edu) with MHSnet (insertion MHSnet site: odtdev.rnd.stone.oz.au); Mon, 06 Nov 1995 15:16:36 +1100 From: daryl@stone.oz.au (Daryl Sayers) X-Mailer: SCO System V Mail (version 3.2) To: postgres@postgres.Berkeley.EDU Date: Mon, 6 Nov 95 10:41:44 AEST Message-ID: <9511061041.aa16227@odtdev.stone.oz.au> Resent-To: postgres-redist@postgres.Berkeley.EDU Resent-Date: Sun, 05 Nov 95 20:17:07 -0800 Resent-XMts: smtp Newsgroups: stone.mlist.postgres Path: daryl From: daryl@stone.oz.au (Daryl Sayers) Subject: Re: Simple retrieve question Organization: Stone Microsystems, NSW, Australia Date: Mon, 6 Nov 1995 00:41:37 GMT Message-ID: X-Newsreader: NN version 6.5.0 #3 References: <9511031223.aa22499@odtdev.stone.oz.au> >O.K. call me lame, but I can't figure it out..... >I have 2 classes, One for Company info and 1 for Contacts. >For every Contact record there is an id that points to the >Company it belongs to. My questions how can I retrieve all >the Companys that do not have a Contact record. O.K. Here is some more information as the kind souls that answered me all suggested similar ideas that I had already tried. retrieve (u.name) from u in company, v in contact where u.id != v.id This doesnt work because it goes through all the Companys and checks against all Contacts. example: Class Company Class Contacts id Company id Contact 1 AAAA 1 Fred Dag 2 BBBB 1 Joe Bloggs 3 CCCC 3 Pete Smith The command above will produce a list: (u.id != v.id) ( 1 != 1 ) Dont Print AAAA (u.id != v.id) ( 2 != 1 ) **** Print BBBB BBBB (u.id != v.id) ( 3 != 1 ) **** Print CCCC CCCC (u.id != v.id) ( 1 != 1 ) Dont Print AAAA (u.id != v.id) ( 2 != 1 ) **** Print BBBB BBBB (u.id != v.id) ( 3 != 1 ) **** Print CCCC CCCC (u.id != v.id) ( 1 != 3 ) **** Print AAAA AAAA (u.id != v.id) ( 2 != 3 ) **** Print BBBB BBBB (u.id != v.id) ( 3 != 3 ) Dont Print CCCC I am using postgres4.2 -- Daryl Sayers Ph: (02) 417 3788 Stone Group Asia Pacific Fax: (02) 417 3741 Unit 20, 380 Eastern Valley Way Email: daryl@stone.oz.au Roseville, 2069 NSW Australia WWW: http://sydney.DIALix.com/~stone ============================================================================== To add/remove yourself to/from the POSTGRES mailing list: send mail with the subject line ADD or DEL to "postgres-request@postgres.Berkeley.EDU". If this fails, send mail to "post_questions@postgres.Berkeley.EDU" and a human will deal with it. DO NOT post to the "postgres" mailing list. ============================================================================== URL: http://s2k-ftp.CS.Berkeley.EDU:8000/postgres/