Received: from maia.hub.org (maia-3.hub.org [200.46.204.243]) by mail.postgresql.org (Postfix) with ESMTP id 12720B5D942 for ; Sun, 15 May 2011 00:00:30 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.243]) (amavisd-maia, port 10024) with ESMTP id 27314-01 for ; Sun, 15 May 2011 03:00:22 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from lo.gmane.org (lo.gmane.org [80.91.229.12]) by mail.postgresql.org (Postfix) with ESMTP id 7F23BB5D91F for ; Sun, 15 May 2011 00:00:22 -0300 (ADT) Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1QLRZ6-0003Bw-KE for pgsql-sql@postgresql.org; Sun, 15 May 2011 05:00:20 +0200 Received: from ip-118-90-140-139.xdsl.xnet.co.nz ([118.90.140.139]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 15 May 2011 05:00:20 +0200 Received: from jasen by ip-118-90-140-139.xdsl.xnet.co.nz with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 15 May 2011 05:00:20 +0200 X-Injected-Via-Gmane: http://gmane.org/ To: pgsql-sql@postgresql.org From: Jasen Betts Subject: Re: self join Date: 15 May 2011 02:36:46 GMT Organization: Dis (not Dat) Organisation Lines: 17 Message-ID: References: <87y629rl34.fsf@kolob.subpolar.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Complaints-To: usenet@dough.gmane.org X-Gmane-NNTP-Posting-Host: ip-118-90-140-139.xdsl.xnet.co.nz X-Face: ?)Aw4rXwN5u0~$nqKj`xPz>xHCwgi^q+^?Ri*+R(&uv2=E1Q0Zk(>h!~o2ID@6{uf8s; a +M[5[U[QT7xFN%^gR"=tuJw%TXXR'Fp~W; (T"1(739R%m0Yyyv*gkGoPA.$b,D.w:z+<'"=-lVT?6 {T?=R^:W5g|E2#EhjKCa+nt":4b}dU7GYB*HBxn&Td$@f%.kl^:7X8rQWd[NTc"P"u6nkisze/Q; 8 "9Z{peQF,w)7UjV$c|RO/mQW/NMgWfr5*$-Z%u46"/00mx-,\R'fLPe.)^ User-Agent: slrn/pre1.0.0-18 (Linux) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.91 tagged_above=-5 required=5 tests=BAYES_00=-1.9, T_RP_MATCHES_RCVD=-0.01 X-Spam-Level: X-Archive-Number: 201105/94 X-Sequence-Number: 35378 On 2011-05-14, Seb wrote: > Hi, > > This probably reflects my confusion with how self joins work. > > Suppose we have this table: > If I want to get a table with records where none of the values in column > b are found in column a, I thought this should do it: use the "NOT IN" operator with a subquery to retch the disallowed values. select * from tmp where a NOT IN (select b from tmp); -- ⚂⚃ 100% natural