Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!cs.utexas.edu!titan!drack From: drack@titan.tsd.arlut.utexas.edu (Dave Rackley) Newsgroups: comp.databases Subject: Re: SQL Duplicate Row Deletion ??? Message-ID: Date: 3 Apr 91 14:30:24 GMT References: <91091.141528SYSPMZT@GECRDVM1.BITNET> <1991Apr3.010838.2063@eng.ufl.edu> Sender: news@titan.tsd.arlut.utexas.edu Organization: Applied Research Laboratories, University of Texas at Austin. Lines: 28 In-reply-to: tsao@helios.tcad.ee.ufl.edu's message of 3 Apr 91 01:08:38 GMT In article <1991Apr3.010838.2063@eng.ufl.edu> tsao@helios.tcad.ee.ufl.edu ( Tsao) writes: >I am now using Ingres, I am surprised that it allows the user to append >duplicated rows (including a null row) into a table unless you define a key >using create unique index. >Would anybody give me an example justifying the need for duplicated tuples >in a table ? I cannot justify the need for them, but in real-time data collection duplicates are often created by multiple sensors at a single source. It then becomes a data reduction/analysis issue to remove duplicates, while recording the fact that duplicate data captures occurred. Why let this happen? Our data is always dirty--we have to clean it up before the customer gets his hands on it! -- DISCLAIMER: I, hereby, disclaim any disclaimer except this disclaimer. +=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=+ | David Rackley | Now comes the really weird part...You know | | Applied Research Laboratories | the part where I know how to tap dance, but | | The University of Texas | only while wearing golf shoes... | | Austin, TX. 78758 | ...Ponderous, man, really ponderous! | +=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=+