Re: LEFT JOIN ... - Mailing list pgsql-sql

From Tom Lane
Subject Re: LEFT JOIN ...
Date
Msg-id 8035.992894175@sss.pgh.pa.us
Whole thread Raw
In response to Re: LEFT JOIN ...  (The Hermit Hacker <scrappy@hub.org>)
Responses Re: LEFT JOIN ...  (The Hermit Hacker <scrappy@hub.org>)
List pgsql-sql
The Hermit Hacker <scrappy@hub.org> writes:
>> Try adding ... AND n.nid = 15748 ...  to the WHERE.

> n.nid is the note id ... nl.id is the contact id ...

Ooops, I misread "n.nid = nl.nid" as "n.nid = nl.id".  Sorry for the
bogus advice.

Try rephrasing as

FROM (note_links nl JOIN notes n ON (n.nid = nl.nid))    LEFT JOIN calendar c ON (n.nid = c.nid)
WHERE ...

The way you were writing it forced the LEFT JOIN to be done first,
whereas what you want is for the note_links-to-notes join to be done
first.  See
http://www.ca.postgresql.org/users-lounge/docs/7.1/postgres/explicit-joins.html
        regards, tom lane


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