Re: equivalence class not working? - Mailing list pgsql-hackers

From Tom Lane
Subject Re: equivalence class not working?
Date
Msg-id 18394.1137448003@sss.pgh.pa.us
Whole thread Raw
In response to equivalence class not working?  (uwcssa <uwcssa@gmail.com>)
Responses Re: equivalence class not working?  (uwcssa <uwcssa@gmail.com>)
List pgsql-hackers
uwcssa <uwcssa@gmail.com> writes:
> I am using postgres 8.1.  In indxpath.c, it says " Note: if Postgres tried
> to optimize queries by forming equivalence
> classes over equi-joined attributes (i.e., if it recognized that
> aqualification such as "where
> a.b=3Dc.d and a.b=3D5" could make use of
>  an index on c.d), then we could use that equivalence class info here with
> joininfo_list to do more complete tests for the usability
> of a partial index.  .....  XXX as of 7.1, equivalence class info *is*
> available."

Are you deliberately ignoring the rest of the comment?
        regards, tom lane


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