pgsql/src/include/optimizer (paths.h planmain.h)

Started by Tom Lane <>about 26 years ago2 messagescomitters
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#1Tom Lane <>
tom_lane___@unknown.user

Date: Sunday, July 23, 2000 @ 23:10:54
Author: tgl

Update of /home/projects/pgsql/cvsroot/pgsql/src/include/optimizer
from hub.org:/home/projects/pgsql/tmp/cvs-serv74468/include/optimizer

Modified Files:
paths.h planmain.h

----------------------------- Log Message -----------------------------

Deduce equality constraints that are implied by transitivity of
mergejoinable qual clauses, and add them to the query quals. For
example, WHERE a = b AND b = c will cause us to add AND a = c.
This is necessary to ensure that it's safe to use these variables
as interchangeable sort keys, which is something 7.0 knows how to do.
Should provide a useful improvement in planning ability, too.

#2Bruce Momjian
bruce@momjian.us
In reply to: Tom Lane <> (#1)
Re: pgsql/src/include/optimizer (paths.h planmain.h)

Date: Sunday, July 23, 2000 @ 23:10:54
Author: tgl

Update of /home/projects/pgsql/cvsroot/pgsql/src/include/optimizer
from hub.org:/home/projects/pgsql/tmp/cvs-serv74468/include/optimizer

Modified Files:
paths.h planmain.h

----------------------------- Log Message -----------------------------

Deduce equality constraints that are implied by transitivity of
mergejoinable qual clauses, and add them to the query quals. For
example, WHERE a = b AND b = c will cause us to add AND a = c.
This is necessary to ensure that it's safe to use these variables
as interchangeable sort keys, which is something 7.0 knows how to do.
Should provide a useful improvement in planning ability, too.

Hard to imagine this didn't happen before.

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