On 08/31/2016 11:43 PM, Andres Freund wrote:
> On 2016-08-31 23:40:46 +0200, Tomas Vondra wrote:
>> It's an improvement (and it's pretty much exactly what I proposed
>> upthread). But it does not solve the problems with pg_statistic for
>> example (each backend needs it's own statistics. So we'd either bloat
>> the pg_statistic (if we manage to solve the problem that the table has
>> the same oid in all backends), or we would need in-memory tuples (just
>> like discussed in the thread so far).
>
> Creating a session private version of pg_statistic would be fairly
> simple.
Sure. I'm just saying it's not as simple as overriding relpath.
ISTM we only need the pg_statistics (as other catalogs are connected to
the pg_class entry), which does not have the dependency issues. Or do we
need other catalogs?
regards
--
Tomas Vondra http://www.2ndQuadrant.com
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