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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Hi Adrian,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Yes zero works fine.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">The syntax is referred to as ‘predicates’ and there are a whole host of them to do basic tests. I have found them extremely useful
in doing data imports from less than reliable third parties.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Marty<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> aw@rationalcommerce.com <aw@rationalcommerce.com>
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<b>Sent:</b> 29 July 2020 08:18<br>
<b>To:</b> Martin Bowes <martin.bowes@ndph.ox.ac.uk>; Ingres lists <info-ingres@lists.planetingres.org><br>
<b>Subject:</b> Re: [Info-ingres] why is an empty string an integer<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt">Morning<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt">If you use zero instead of 1 do you get the same?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt">I must admit i have not seen that 'when a is integer/float' syntax before.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt">But then i use openroad so our syntax is about 20 years behind.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt">Adrian<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt">------ Original message------<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt">From: </span></b><span style="font-size:10.0pt">Martin Bowes<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt">Date: </span></b><span style="font-size:10.0pt">Wed, 29 Jul 2020 08:01<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt">To: </span></b><span style="font-size:10.0pt">Ingres lists;<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt">Cc: </span></b><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt">Subject:</span></b><span style="font-size:10.0pt">[Info-ingres] why is an empty string an integer<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.0pt">Hi All,<o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.0pt"> <o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.0pt">I may have come across this before, but it’s early and I haven’t had my coffee.<o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.0pt"> <o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">declare global temporary table fred(</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif"> a varchar(20)</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">) on commit preserve rows with norecovery;</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">Executing . . .</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif"> </span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">continue</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">* * insert into fred values (null), (''), ('1'), ('13-jan-2020');</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">Executing . . .</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif"> </span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">(4 rows)</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">continue</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">* * * * * * * * select case when a is null then 'null'</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif"> when a = '' then 'empty string'</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif"> else a end as data,</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif"> case when a is integer then 'integer' else 'not integer' end as is_integer,</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif"> case when a is float then 'float' else 'not float' end as is_float,</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif"> case when a is ansidate then 'ansidate' else 'not ansidate' end as is_ansidate</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">from fred;</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">Executing . . .</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif"> </span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif"> </span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">┌────────────────────┬───────────┬─────────┬────────────┐</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">│data │is_integer │is_float │is_ansidate │</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">├────────────────────┼───────────┼─────────┼────────────┤</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">│null │not integer│not float│not ansidate│</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">│empty string │<span style="background:yellow;mso-highlight:yellow">integer │float</span> │not ansidate│</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">│1 │integer │float │not ansidate│</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">│13-jan-2020 │not integer│not float│ansidate │</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">└────────────────────┴───────────┴─────────┴────────────┘</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">(4 rows)</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Lucida Console",serif">continue</span><span style="font-size:10.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.0pt"> <o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.0pt">Now the tests with nulls behave as I expect. But the empty string cases I did not expect. Is this a bug? Documented behaviour?<o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.0pt"> <o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.0pt">Martin Bowes<o:p></o:p></span></p>
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