Support parallel aggregation.

Parallel workers can now partially aggregate the data and pass the
transition values back to the leader, which can combine the partial
results to produce the final answer.

David Rowley, based on earlier work by Haribabu Kommi.  Reviewed by
Álvaro Herrera, Tomas Vondra, Amit Kapila, James Sewell, and me.

5 files changed, 5 insertions, 1 deletions

diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index 45898343057..6b5d1d6efce 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -1233,6 +1233,7 @@ _copyAggref(const Aggref *from)
 
 	COPY_SCALAR_FIELD(aggfnoid);
 	COPY_SCALAR_FIELD(aggtype);
+	COPY_SCALAR_FIELD(aggoutputtype);
 	COPY_SCALAR_FIELD(aggcollid);
 	COPY_SCALAR_FIELD(inputcollid);
 	COPY_NODE_FIELD(aggdirectargs);
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index b9c39594283..87eb859e05e 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -192,6 +192,7 @@ _equalAggref(const Aggref *a, const Aggref *b)
 {
 	COMPARE_SCALAR_FIELD(aggfnoid);
 	COMPARE_SCALAR_FIELD(aggtype);
+	COMPARE_SCALAR_FIELD(aggoutputtype);
 	COMPARE_SCALAR_FIELD(aggcollid);
 	COMPARE_SCALAR_FIELD(inputcollid);
 	COMPARE_NODE_FIELD(aggdirectargs);
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index b4ea440f052..46af8721161 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -57,7 +57,7 @@ exprType(const Node *expr)
 			type = ((const Param *) expr)->paramtype;
 			break;
 		case T_Aggref:
-			type = ((const Aggref *) expr)->aggtype;
+			type = ((const Aggref *) expr)->aggoutputtype;
 			break;
 		case T_GroupingFunc:
 			type = INT4OID;
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 1144a4c1c71..32d03f7f257 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -1033,6 +1033,7 @@ _outAggref(StringInfo str, const Aggref *node)
 
 	WRITE_OID_FIELD(aggfnoid);
 	WRITE_OID_FIELD(aggtype);
+	WRITE_OID_FIELD(aggoutputtype);
 	WRITE_OID_FIELD(aggcollid);
 	WRITE_OID_FIELD(inputcollid);
 	WRITE_NODE_FIELD(aggdirectargs);
diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c
index d63de7f9073..6db0492e152 100644
--- a/src/backend/nodes/readfuncs.c
+++ b/src/backend/nodes/readfuncs.c
@@ -552,6 +552,7 @@ _readAggref(void)
 
 	READ_OID_FIELD(aggfnoid);
 	READ_OID_FIELD(aggtype);
+	READ_OID_FIELD(aggoutputtype);
 	READ_OID_FIELD(aggcollid);
 	READ_OID_FIELD(inputcollid);
 	READ_NODE_FIELD(aggdirectargs);