I want to test my own selectivity function against future stats collector.
Is this a right way to update statistic used by planner ?
update pg_statistic set
00,10001] where starelid=950855 and staattnum = 21;
stadistinct values total, stakind3 is my custom STATISTIC_KIND, stanumber3
are frequencies of stavalues3.
How to add custom statistic kind for 1-dim array of integers (_int4) ?
Currently it uses standard compute_scalar_stats (commands/analyze.c).
Custom statistic is needed to count selectivity for GIST built by
It should be gathered only for 1-dim arrays and contain most-common values
met in among all arrays,
Distinct values among all arrays etc.
Generally, it can be gathered on anyarray(not only _int4), but it's ok for
me (yet) to have it working for _int4 1-dim only.
Pitifully, I have no idea what is the right way of putting such thing into
Should I add switches into analyze.c or there exist a better way ?
Maybe one could sketch out the structure of what is to be done.
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