Re: Multi-column distinctness.

<p dir="ltr"><br /> On Sep 6, 2015 10:31, "Tomas Vondra" <<a
href="mailto:tomas.vondra@2ndquadrant.com">tomas.vondra@2ndquadrant.com</a>>wrote:<br /> ><br /> > 5)
syntax<br/> > ---------<br /> > The syntax might be one of the pain points if we eventually decide to commit the
multivariatestats patch. I have no intention in blocking this patch for that reasons, but if we might design the syntax
tomake it compatible with the multivariate patch, that'd be nice. But it seems to me the syntax is pretty much the
same,no?<br /> ><br /> > I.e. it uses<br /> ><br /> >     ADD STATISTICS (options) ON (columns)<br />
><br/> > just like the multivariate patch, no? Well, it doesn't really check the stattypes in
ATExecAddDropMvStatisticsexcept for checking there's a single entry, but the syntax seems OK.<br /> ><br /> > BTW
mixingADD and DROP in ATExecAddDropMvStatistics seems a bit confusing. Maybe two separate methods would be better?<br
/>><p dir="ltr">BTW one more comment about the syntax - you ran into the same conflict between "ADD [COLUMN] column"
and"ADD STATISTICS" like I did, but you solved it by making the COLUMN required while I made STATISTICS keyword.<p
dir="ltr">I'mnot enthusiastic about the keyword thing, but making the COLUMN required is certainly much worse as it
breaksmany existing scripts. The keyword inky breaks cases that manipulate "statistics" column.<p dir="ltr">If any of
thisis unacceptable, then we probably need to come up with a different syntax.<p dir="ltr">Regards<p dir="ltr">-- <br
/>Tomas Vondra                   <a href="http://www.2ndQuadrant.com/">http://www.2ndQuadrant.com/</a><p
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