Re: Selectivity estimation for intarray - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Selectivity estimation for intarray
Date
Msg-id 35337.1430323526@sss.pgh.pa.us
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In response to Re: Selectivity estimation for intarray  (Stephen Frost <sfrost@snowman.net>)
List pgsql-hackers
Stephen Frost <sfrost@snowman.net> writes:
> * Tom Lane (tgl@sss.pgh.pa.us) wrote:
>> For the specific cases you mention, perhaps it would be all right if we
>> taught plancache.c to blow away *all* cached plans upon seeing any change
>> in pg_operator; but that seems like a brute-force solution.

> Agreed that it is- but is that really a problem...?

Perhaps it isn't; we certainly have assumptions that pg_amop, for
instance, changes seldom enough that it's not worth tracking individual
changes.  The same might be true of pg_operator.  I'm not sure though.

The core point I'm trying to make is that making pg_operator entries
mutable is something that's going to require very careful review.
        regards, tom lane



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