Thread: pgsql-server/src backend/optimizer/plan/planne ...

pgsql-server/src backend/optimizer/plan/planne ...

From
tgl@svr1.postgresql.org (Tom Lane)
Date:
CVSROOT:    /cvsroot
Module name:    pgsql-server
Changes by:    tgl@svr1.postgresql.org    04/04/07 15:17:25

Modified files:
    src/backend/optimizer/plan: planner.c
    src/backend/optimizer/prep: prepunion.c
    src/include/optimizer: prep.h

Log message:
    Extend set-operation planning to keep track of the sort ordering induced
    by the set operation, so that redundant sorts at higher levels can be
    avoided.  This was foreseen a good while back, but not done.  Per request
    from Karel Zak.