v2-0001-Teach-CopyFrom-to-use-ModifyTableState-for-tuple-.patch

From 187683f6ea153e8be1a5c067b3546e70b15ccd47 Mon Sep 17 00:00:00 2001
From: amit <amitlangote09@gmail.com>
Date: Tue, 19 Dec 2017 10:43:45 +0900
Subject: [PATCH v2 1/4] Teach CopyFrom to use ModifyTableState for
 tuple-routing

This removes all fields of CopyStateData that were meant for
tuple routing and instead uses ModifyTableState that has all those
fields, including transition_tupconv_maps.  In COPY's case,
transition_tupconv_maps is only required if tuple routing is being
used, so it's safe.
---
 src/backend/commands/copy.c | 33 ++++++++++++++++++---------------
 1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index 6bfca2a4af..242dc56d87 100644
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@@ -166,11 +166,7 @@ typedef struct CopyStateData
 	bool		volatile_defexprs;	/* is any of defexprs volatile? */
 	List	   *range_table;
 
-	/* Tuple-routing support info */
-	PartitionTupleRouting *partition_tuple_routing;
-
 	TransitionCaptureState *transition_capture;
-	TupleConversionMap **transition_tupconv_maps;
 
 	/*
 	 * These variables are used to reduce overhead in textual COPY FROM.
@@ -2286,6 +2282,7 @@ CopyFrom(CopyState cstate)
 	ResultRelInfo *resultRelInfo;
 	ResultRelInfo *saved_resultRelInfo = NULL;
 	EState	   *estate = CreateExecutorState(); /* for ExecConstraints() */
+	ModifyTableState *mtstate = makeNode(ModifyTableState);
 	ExprContext *econtext;
 	TupleTableSlot *myslot;
 	MemoryContext oldcontext = CurrentMemoryContext;
@@ -2304,6 +2301,8 @@ CopyFrom(CopyState cstate)
 	Size		bufferedTuplesSize = 0;
 	int			firstBufferedLineNo = 0;
 
+	PartitionTupleRouting *proute = NULL;
+
 	Assert(cstate->rel);
 
 	/*
@@ -2469,10 +2468,15 @@ CopyFrom(CopyState cstate)
 	 */
 	if (cstate->rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
 	{
-		PartitionTupleRouting *proute;
+		ModifyTable *node = makeNode(ModifyTable);
 
-		proute = cstate->partition_tuple_routing =
-			ExecSetupPartitionTupleRouting(NULL, cstate->rel, 1, estate);
+		/* Just need make this field appear valid. */
+		node->nominalRelation = 1;
+		mtstate->ps.plan = (Plan *) node;
+		mtstate->ps.state = estate;
+		mtstate->resultRelInfo = resultRelInfo;
+		proute = mtstate->mt_partition_tuple_routing =
+			ExecSetupPartitionTupleRouting(mtstate, cstate->rel, 1, estate);
 
 		/*
 		 * If we are capturing transition tuples, they may need to be
@@ -2484,11 +2488,11 @@ CopyFrom(CopyState cstate)
 		{
 			int			i;
 
-			cstate->transition_tupconv_maps = (TupleConversionMap **)
+			mtstate->mt_transition_tupconv_maps = (TupleConversionMap **)
 				palloc0(sizeof(TupleConversionMap *) * proute->num_partitions);
 			for (i = 0; i < proute->num_partitions; ++i)
 			{
-				cstate->transition_tupconv_maps[i] =
+				mtstate->mt_transition_tupconv_maps[i] =
 					convert_tuples_by_name(RelationGetDescr(proute->partitions[i]->ri_RelationDesc),
 										   RelationGetDescr(cstate->rel),
 										   gettext_noop("could not convert row type"));
@@ -2509,7 +2513,7 @@ CopyFrom(CopyState cstate)
 	if ((resultRelInfo->ri_TrigDesc != NULL &&
 		 (resultRelInfo->ri_TrigDesc->trig_insert_before_row ||
 		  resultRelInfo->ri_TrigDesc->trig_insert_instead_row)) ||
-		cstate->partition_tuple_routing != NULL ||
+		mtstate->mt_partition_tuple_routing != NULL ||
 		cstate->volatile_defexprs)
 	{
 		useHeapMultiInsert = false;
@@ -2584,11 +2588,10 @@ CopyFrom(CopyState cstate)
 		ExecStoreTuple(tuple, slot, InvalidBuffer, false);
 
 		/* Determine the partition to heap_insert the tuple into */
-		if (cstate->partition_tuple_routing)
+		if (cstate->rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
 		{
 			int			leaf_part_index;
 			TupleConversionMap *map;
-			PartitionTupleRouting *proute = cstate->partition_tuple_routing;
 
 			/*
 			 * Away we go ... If we end up not finding a partition after all,
@@ -2651,7 +2654,7 @@ CopyFrom(CopyState cstate)
 					 */
 					cstate->transition_capture->tcs_original_insert_tuple = NULL;
 					cstate->transition_capture->tcs_map =
-						cstate->transition_tupconv_maps[leaf_part_index];
+						mtstate->mt_transition_tupconv_maps[leaf_part_index];
 				}
 				else
 				{
@@ -2832,8 +2835,8 @@ CopyFrom(CopyState cstate)
 	ExecCloseIndices(resultRelInfo);
 
 	/* Close all the partitioned tables, leaf partitions, and their indices */
-	if (cstate->partition_tuple_routing)
-		ExecCleanupTupleRouting(cstate->partition_tuple_routing);
+	if (proute)
+		ExecCleanupTupleRouting(proute);
 
 	/* Close any trigger target relations */
 	ExecCleanUpTriggerState(estate);
-- 
2.11.0