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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoPlainText>I was more curious about WTF ii_dv_desc was all about:<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><img width=1299 height=449 style='width:13.5312in;height:4.677in' id="Picture_x0020_1" src="cid:image001.png@01D6ADFA.4050BA70"><o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>But I then found this:<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><a href="http://www.databaseteam.org/10-database/7ae0587cf0276f06.htm">http://www.databaseteam.org/10-database/7ae0587cf0276f06.htm</a><o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><span lang=EN-US style='mso-fareast-language:EN-GB'>-----Original Message-----<br>From: info-ingres-bounces@lists.planetingres.org <info-ingres-bounces@lists.planetingres.org> On Behalf Of Martin Bowes<br>Sent: 29 October 2020 13:14<br>To: Karl Schendel <schendel@kbcomputer.com><br>Cc: info-ingres@lists.planetingres.org<br>Subject: Re: [Info-ingres] Question on min() and nullability</span></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Of course, thanks Karl.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>-----Original Message-----<o:p></o:p></p><p class=MsoPlainText>From: Karl Schendel <<a href="mailto:schendel@kbcomputer.com"><span style='color:windowtext;text-decoration:none'>schendel@kbcomputer.com</span></a>> <o:p></o:p></p><p class=MsoPlainText>Sent: 29 October 2020 13:11<o:p></o:p></p><p class=MsoPlainText>To: Martin Bowes <<a href="mailto:martin.bowes@ndph.ox.ac.uk"><span style='color:windowtext;text-decoration:none'>martin.bowes@ndph.ox.ac.uk</span></a>><o:p></o:p></p><p class=MsoPlainText>Cc: <a href="mailto:info-ingres@lists.planetingres.org"><span style='color:windowtext;text-decoration:none'>info-ingres@lists.planetingres.org</span></a><o:p></o:p></p><p class=MsoPlainText>Subject: Re: [Info-ingres] Question on min() and nullability<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>> On Oct 29, 2020, at 9:08 AM, Martin Bowes <<a href="mailto:martin.bowes@ndph.ox.ac.uk"><span style='color:windowtext;text-decoration:none'>martin.bowes@ndph.ox.ac.uk</span></a>> wrote:<o:p></o:p></p><p class=MsoPlainText>> <o:p></o:p></p><p class=MsoPlainText>> select ii_dv_desc(min(a)) from session.test Executing . . .<o:p></o:p></p><p class=MsoPlainText>> <o:p></o:p></p><p class=MsoPlainText>> <o:p></o:p></p><p class=MsoPlainText>> ┌──────────────────────────────────────────────────────────────┐<o:p></o:p></p><p class=MsoPlainText>> │col1 │<o:p></o:p></p><p class=MsoPlainText>> <span style='font-family:"Arial",sans-serif'>├</span>──────────────────────────────────────────────────────────────<span style='font-family:"Arial",sans-serif'>┤</span><o:p></o:p></p><p class=MsoPlainText>> │nullable ingresdate │<o:p></o:p></p><p class=MsoPlainText>> └──────────────────────────────────────────────────────────────┘<o:p></o:p></p><p class=MsoPlainText>> (1 row)<o:p></o:p></p><p class=MsoPlainText>> <o:p></o:p></p><p class=MsoPlainText>> How can the min of a non nullable field ever itself be a null?<o:p></o:p></p><p class=MsoPlainText>> <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Because it's an aggregate. min can be null if there are no rows.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Karl<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>_______________________________________________<o:p></o:p></p><p class=MsoPlainText>Info-ingres mailing list<o:p></o:p></p><p class=MsoPlainText><a href="mailto:Info-ingres@lists.planetingres.org"><span style='color:windowtext;text-decoration:none'>Info-ingres@lists.planetingres.org</span></a><o:p></o:p></p><p class=MsoPlainText><a href="https://lists.planetingres.org/mailman/listinfo/info-ingres"><span style='color:windowtext;text-decoration:none'>https://lists.planetingres.org/mailman/listinfo/info-ingres</span></a><o:p></o:p></p><p class=MsoPlainText>_______________________________________________<o:p></o:p></p><p class=MsoPlainText>Info-ingres mailing list<o:p></o:p></p><p class=MsoPlainText><a href="mailto:Info-ingres@lists.planetingres.org"><span style='color:windowtext;text-decoration:none'>Info-ingres@lists.planetingres.org</span></a><o:p></o:p></p><p class=MsoPlainText><a href="https://lists.planetingres.org/mailman/listinfo/info-ingres"><span style='color:windowtext;text-decoration:none'>https://lists.planetingres.org/mailman/listinfo/info-ingres</span></a><o:p></o:p></p></div></body></html>