pgsql/src/backend/optimizer/path (pathkeys.c)

Date: Sunday, July 23, 2000 @ 23:10:57
Author: tgl

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

Modified Files:
pathkeys.c

----------------------------- 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.