<div dir="ltr">Greetings,<div><br></div><div>I'm happy to take a stab at it! If anyone sees anything I'm missing please feel free to add your thoughts.<br><div><br></div><div>Looking at the generated SQL:</div><div><br></div><div><font face="monospace, monospace"><span style="font-size:12.8px">SELECT</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> COUNT( * )</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> FROM (</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> SELECT</span></font></div><div><font face="monospace, monospace"> <a href="http://me.id/" rel="noreferrer" target="_blank" style="font-size:12.8px">me.id</a></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> ,me.valid_from</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> ,me.valid_till</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> ,me.removed</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> ,me.provisioning_agreement_id</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> ,me.resource_piece_id</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> ,me.service_type_id</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> ,me.service_level_id</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"><b> ,me.quantity</b></span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"><b> ,me.quantity</b></span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> FROM provisioning_obligation me</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> GROUP BY quantity</span></font></div><div><font face="monospace, monospace"><span style="font-size:12.8px"> ) me</span></font><br></div><div><br></div><div>We can see that the quantity column is appearing twice (which is what is generating that Duplicate column name, because the derived table has the same column twice so it can't be "fed into" the SELECT COUNT(*) ). Is it possible you copy pasted the quantity definition in the result source an extra time? Alternatively, how are you generating the $resultset you are using, is it possible you are tacking on an extra quantity then, or are you querying the provisioning_obligation result source directly?</div><div><br></div><div>More importantly though, I'm curious as to what information you are actually trying to get. You want a distinct count of quantities from the provisioning_obligation table? I'm not sure the utility of that information, but a better way to answer that question would be to use a SELECT COUNT( DISTINCT quantity ), there is a great example in the docs at:</div><div><br></div><div><a href="http://search.cpan.org/dist/DBIx-Class/lib/DBIx/Class/Manual/Cookbook.pod#SELECT_COUNT(DISTINCT_colname)">http://search.cpan.org/dist/DBIx-Class/lib/DBIx/Class/Manual/Cookbook.pod#SELECT_COUNT(DISTINCT_colname)</a></div><div><br></div><div>Hopefully you find this helpful.</div><div><br></div><div>Best Regards,</div><div>Robert Stone</div><div><br></div></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Oct 10, 2017 at 6:20 AM, Vladimir Melnik <span dir="ltr"><<a href="mailto:v.melnik@uplink.ua" target="_blank">v.melnik@uplink.ua</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Dear colleagues,<br>
<br>
Here's a little snippet of the code:<br>
$resultset<br>
->search(undef, { group_by => [ qw(quantity) ] })<br>
->count;<br>
<br>
It produces the following exception:<br>
DBI Exception: DBD::mysql::st execute failed: Duplicate column name 'quantity' [for Statement "SELECT COUNT( * ) FROM (SELECT <a href="http://me.id" rel="noreferrer" target="_blank">me.id</a>, me.valid_from, me.valid_till, me.removed, me.provisioning_agreement_id, me.resource_piece_id, me.service_type_id, me.service_level_id, me.quantity, me.quantity FROM provisioning_obligation me GROUP BY quantity) me"] at /home/mmkeeper/perl5/perlbrew/<wbr>perls/perl-5.24.0/lib/site_<wbr>perl/5.24.0/DBIx/Class/Schema.<wbr>pm line 1118.<br>
<br>
What is the best way to avoid that?<br>
<br>
Thanks in advance!<br>
<span class="HOEnZb"><font color="#888888"><br>
--<br>
V.Melnik<br>
<br>
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