Re: plan time of MASSIVE partitioning ... - Mailing list pgsql-hackers

From Tom Lane
Subject Re: plan time of MASSIVE partitioning ...
Date
Msg-id 6006.1283966378@sss.pgh.pa.us
Whole thread Raw
In response to Re: plan time of MASSIVE partitioning ...  (Boszormenyi Zoltan <zb@cybertec.at>)
Responses Re: plan time of MASSIVE partitioning ...  (Boszormenyi Zoltan <zb@cybertec.at>)
List pgsql-hackers
Boszormenyi Zoltan <zb@cybertec.at> writes:
> Tom Lane �rta:
>> AFAIR, canonical pathkeys are the *only* thing in the planner where pure
>> pointer equality is interesting.  So I doubt this hack is of any use for
>> EquivalenceClass, even if the lists were likely to be long which they
>> aren't.

> No, for EquivalanceClass->ec_member, I need to do something
> funnier, like implement compare(Node *, Node *) and use that
> instead of equal(Node *, Node *)... Something like nodeToString()
> on both Node * and strcmp() the resulting strings.

Well, (a) that doesn't work (hint: there are fields in nodes that are
intentionally ignored by equal()), and (b) I still don't believe that
there's an actual bottleneck there.  ECs generally aren't very big.
        regards, tom lane


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