Article View: borland.public.interbase.sql
Article #11387Re: Selecting row in which a column value is maximum
From: Craig Stuntz TeamB
Date: Mon, 25 Nov 2002 19:51
Date: Mon, 25 Nov 2002 19:51
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In article <3de27571$1@newsgroups.borland.com>, eddielee@tropicsoft.com says... > If the index is sorted based on the index value, which seems pretty natural > so that a particular record can be found easily based on its index, then > going to the last record of the index of an ascending index will give the > max value. > Keep in mind that the last record pointed to in the index might not be visible to the current transaction. In which case you are stuck with trying to walk the index backwards -- which is hard when we're talking about a prefix-compressed tree structure. -Craig -- Craig Stuntz [TeamB] � Vertex Systems Corp. � Columbus, OH Delphi/InterBase Weblog : http://delphi.weblogs.com InterBase Perf. Monitor : http://delphi.weblogs.com/IBPerformanceMonitor InterBase PLANalyzer 1.1: http://delphi.weblogs.com/IBPLANalyzer
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X-Google-Language: ENGLISH,ASCII X-Google-Thread: 114a0e,60a1aedc82f6444 X-Google-Attributes: gid114a0e,public X-Google-ArrivalTime: 2002-11-25 12:07:37 PST From: Craig Stuntz [TeamB] <cstuntz@nospamplease.com (but use vertexsoftware to email)> Newsgroups: borland.public.interbase.sql Subject: Re: Selecting row in which a column value is maximum Date: Mon, 25 Nov 2002 14:51:16 -0500 Message-ID: <MPG.184c493d33d5246b98a267@newsgroups.borland.com> References: <3de051cf@newsgroups.borland.com> <3de0d0f0$1@newsgroups.borland.com> <MPG.184c120210a6b55a98a253@newsgroups.borland.com> <3de24925@newsgroups.borland.com> <MPG.184c1b6154274d7b98a260@newsgroups.borland.com> <3de27571$1@newsgroups.borland.com> Organization: Vertex Systems Corporation X-Newsreader: MicroPlanet Gravity v2.60 NNTP-Posting-Host: 65.86.87.242 X-Trace: newsgroups.borland.com 1038253782 65.86.87.242 (25 Nov 2002 11:49:42 -0800) Lines: 19 Path: arc1-ca.pugleaf.net!archiver1.google.com!news1.google.com!sn-xit-02!sn-xit-05!sn-xit-01!sn-xit-04!supernews.com!news.maxwell.syr.edu!nntp-relay.ihug.net!newsfeeds.ihug.co.nz!ihug.co.nz!newsgroups.borland.com!not-for-mail