So I've heard from Magnus Hagander today IRL at our Stockholm PostgreSQL User Group meeting where we discussed this idea. He told me the overhead in the statistics collector is mainly when reading from it, not that much when writing to it.
Magnus idea was to first optimize the collector to make it less of a problem to collect more data. Sounds like a good thing to do, but maybe more data in it wouldn't be a problem as long as you don't read too often from it?
On Mon 8 Jun 2015 at 18:48 Robert Haas <
robertmhaas@gmail.com> wrote:
On Fri, Jun 5, 2015 at 7:51 AM, Joel Jacobson <joel@trustly.com> wrote:
> Would others find it useful to see per column statistics about accesses to
> specific columns?
A probably serious and maybe not entirely obvious problem with this is
that it would increase the amount of statistical information we keep
by a pretty large multiple. How many columns do you have in a typical
table? 20-30? That's a lot of data for a statistics collector that,
regrettably, is already overloaded.
--
Robert Haas
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