aboutsummaryrefslogtreecommitdiff
path: root/src/backend/executor/nodeBitmapAnd.c
diff options
context:
space:
mode:
authorTom Lane <tgl@sss.pgh.pa.us>2005-08-27 22:13:44 +0000
committerTom Lane <tgl@sss.pgh.pa.us>2005-08-27 22:13:44 +0000
commit4e5fbb34b361102df41642a6ed9676b8b6a1e75f (patch)
tree56acd956f301ecd6f33904d5ac05d984ac6bd413 /src/backend/executor/nodeBitmapAnd.c
parent9e56c5a4cff7edb145729c7ba2b19dd8cf1c45cf (diff)
downloadpostgresql-4e5fbb34b361102df41642a6ed9676b8b6a1e75f.tar.gz
postgresql-4e5fbb34b361102df41642a6ed9676b8b6a1e75f.zip
Change the division of labor between grouping_planner and query_planner
so that the latter estimates the number of groups that grouping will produce. This is needed because it is primarily query_planner that makes the decision between fast-start and fast-finish plans, and in the original coding it was unable to make more than a crude rule-of-thumb choice when the query involved grouping. This revision helps us make saner choices for queries like SELECT ... GROUP BY ... LIMIT, as in a recent example from Mark Kirkwood. Also move the responsibility for canonicalizing sort_pathkeys and group_pathkeys into query_planner; this information has to be available anyway to support the first change, and doing it this way lets us get rid of compare_noncanonical_pathkeys entirely.
Diffstat (limited to 'src/backend/executor/nodeBitmapAnd.c')
0 files changed, 0 insertions, 0 deletions