Re: Understanding bad estimate (related to FKs?)

From: Michael Lewis <mlewis(at)entrata(dot)com>
To: Philip Semanchuk <philip(at)americanefficient(dot)com>
Cc: Guillaume Lelarge <guillaume(at)lelarge(dot)info>, Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com>, Justin Pryzby <pryzby(at)telsasoft(dot)com>, postgres performance list <pgsql-performance(at)postgresql(dot)org>
Subject: Re: Understanding bad estimate (related to FKs?)
Date: 2020-11-02 23:09:52
Message-ID: CAHOFxGrUA2QJLLfF_fEWhyvh=e+J6C5FCDiOJvdk+5QZGj0W4g@mail.gmail.com
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>
> The query I asked about in the original post of this thread has 13
> relations in it. IIUC, that's 13! or > 6 billion possible plans. How did
> the planner pick one plan out of 6 billion? I'm curious, both for practical
> purposes (I want my query to run well) and also because it's fascinating.
>

Have you increased geqo_threshold and join_collapse_limit from the defaults?

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