Add missing call to ExecReScanGatherMerge.

Amit Kapila

Discussion: http://postgr.es/m/CAA4eK1KeQWZOoDmDmGMwuqzPW9JhRS+ditQVFdAfGjNmMZzqMQ@mail.gmail.com

src/backend/executor/execAmi.c

@@ -26,6 +26,7 @@
 #include "executor/nodeForeignscan.h"
 #include "executor/nodeFunctionscan.h"
 #include "executor/nodeGather.h"
+#include "executor/nodeGatherMerge.h"
 #include "executor/nodeGroup.h"
 #include "executor/nodeGroup.h"
 #include "executor/nodeHash.h"
@@ -172,6 +173,10 @@ ExecReScan(PlanState *node)
 			ExecReScanGather((GatherState *) node);
 			break;
 
+		case T_GatherMergeState:
+			ExecReScanGatherMerge((GatherMergeState *) node);
+			break;
+
 		case T_IndexScanState:
 			ExecReScanIndexScan((IndexScanState *) node);
 			break;