Allow aggregate transition states to be serialized and deserialized.

This is necessary infrastructure for supporting parallel aggregation
for aggregates whose transition type is "internal".  Such values
can't be passed between cooperating processes, because they are
just pointers.

David Rowley, reviewed by Tomas Vondra and by me.

2 files changed, 3 insertions, 2 deletions

diff --git a/src/include/optimizer/pathnode.h b/src/include/optimizer/pathnode.h
index 1744ff058e8..acc827de488 100644
--- a/src/include/optimizer/pathnode.h
+++ b/src/include/optimizer/pathnode.h
@@ -171,7 +171,8 @@ extern AggPath *create_agg_path(PlannerInfo *root,
 				const AggClauseCosts *aggcosts,
 				double numGroups,
 				bool combineStates,
-				bool finalizeAggs);
+				bool finalizeAggs,
+				bool serialStates);
 extern GroupingSetsPath *create_groupingsets_path(PlannerInfo *root,
 						 RelOptInfo *rel,
 						 Path *subpath,
diff --git a/src/include/optimizer/planmain.h b/src/include/optimizer/planmain.h
index 596ffb3d175..1f96e27034c 100644
--- a/src/include/optimizer/planmain.h
+++ b/src/include/optimizer/planmain.h
@@ -58,7 +58,7 @@ extern bool is_projection_capable_plan(Plan *plan);
 /* External use of these functions is deprecated: */
 extern Sort *make_sort_from_sortclauses(List *sortcls, Plan *lefttree);
 extern Agg *make_agg(List *tlist, List *qual, AggStrategy aggstrategy,
-		 bool combineStates, bool finalizeAggs,
+		 bool combineStates, bool finalizeAggs, bool serialStates,
 		 int numGroupCols, AttrNumber *grpColIdx, Oid *grpOperators,
 		 List *groupingSets, List *chain,
 		 double dNumGroups, Plan *lefttree);