v18_masahiko_fix.patch

diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index 9e12adb81a1..eac501753c8 100644
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@@ -252,16 +252,14 @@ DoCopy(ParseState *pstate, const CopyStmt *stmt,
 			 * COPY retrieves rows from only the target table not any
 			 * inheritance children, the same as when RLS doesn't apply.
 			 *
-			 * However, when COPY data from a partitioned table, we should not
-			 * use "ONLY", since we also need to retrieve rows from its child
-			 * partitions too.
+			 * However, when copying data from a partitioned table, we don't
+			 * not use "ONLY", since we need to retrieve rows from its
+			 * descendant tables too.
 			 */
 			from = makeRangeVar(get_namespace_name(RelationGetNamespace(rel)),
 								pstrdup(RelationGetRelationName(rel)),
 								-1);
-			from->inh = false;	/* apply ONLY */
-			if (get_rel_relkind(relid) == RELKIND_PARTITIONED_TABLE)
-				from->inh = true;
+			from->inh = (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
 
 			/* Build query */
 			select = makeNode(SelectStmt);
diff --git a/src/backend/commands/copyto.c b/src/backend/commands/copyto.c
index 74497240105..a1919c6db43 100644
--- a/src/backend/commands/copyto.c
+++ b/src/backend/commands/copyto.c
@@ -84,11 +84,11 @@ typedef struct CopyToStateData
 	List	   *attnumlist;		/* integer list of attnums to copy */
 	char	   *filename;		/* filename, or NULL for STDOUT */
 	bool		is_program;		/* is 'filename' a program to popen? */
-	List	   *partitions;		/* OID list of partitions to copy data from */
 	copy_data_dest_cb data_dest_cb; /* function for writing data */
 
 	CopyFormatOptions opts;
 	Node	   *whereClause;	/* WHERE condition (or NULL) */
+	List	   *partitions;		/* OID list of partitions to copy data from */
 
 	/*
 	 * Working state
@@ -1160,9 +1160,9 @@ CopyRelationTo(CopyToState cstate, Relation rel, Relation root_rel, uint64 *proc
 	slot = table_slot_create(rel, NULL);
 
 	/*
-	 * A partition's rowtype might differ from the root table's. If we are
-	 * exporting partition data here, we must convert it back to the root
-	 * table's rowtype.
+	 * If we are exporting partition data here, we check if converting tuples
+	 * to the root table's rowtype, because a partition might have column
+	 * order different than its root table.
 	 */
 	if (root_rel != NULL)
 	{
@@ -1182,7 +1182,7 @@ CopyRelationTo(CopyToState cstate, Relation rel, Relation root_rel, uint64 *proc
 			copyslot = execute_attr_map_slot(map, slot, root_slot);
 		else
 		{
-			/* Deconstruct the tuple ... */
+			/* Deconstruct the tuple */
 			slot_getallattrs(slot);
 			copyslot = slot;
 		}
diff --git a/src/test/regress/expected/copy.out b/src/test/regress/expected/copy.out
index af01e84cea1..24e0f472f14 100644
--- a/src/test/regress/expected/copy.out
+++ b/src/test/regress/expected/copy.out
@@ -374,6 +374,8 @@ id
 1
 DROP MATERIALIZED VIEW copytest_mv;
 -- Tests for COPY TO with partitioned tables.
+-- The child table pp_2 has a different column order than the root table pp.
+-- Check if COPY TO exports tuples as the root table's column order.
 CREATE TABLE pp (id int,val int) PARTITION BY RANGE (id);
 CREATE TABLE pp_1 (val int, id int) PARTITION BY RANGE (id);
 CREATE TABLE pp_2 (id int, val int) PARTITION BY RANGE (id);
diff --git a/src/test/regress/sql/copy.sql b/src/test/regress/sql/copy.sql
index 56d506ad4c6..676a8b342b5 100644
--- a/src/test/regress/sql/copy.sql
+++ b/src/test/regress/sql/copy.sql
@@ -407,16 +407,15 @@ COPY copytest_mv(id) TO stdout WITH (header);
 DROP MATERIALIZED VIEW copytest_mv;
 
 -- Tests for COPY TO with partitioned tables.
+-- The child table pp_2 has a different column order than the root table pp.
+-- Check if COPY TO exports tuples as the root table's column order.
 CREATE TABLE pp (id int,val int) PARTITION BY RANGE (id);
 CREATE TABLE pp_1 (val int, id int) PARTITION BY RANGE (id);
 CREATE TABLE pp_2 (id int, val int) PARTITION BY RANGE (id);
 ALTER TABLE pp ATTACH PARTITION pp_1 FOR VALUES FROM (1) TO (5);
 ALTER TABLE pp ATTACH PARTITION pp_2 FOR VALUES FROM (5) TO (10);
-
 CREATE TABLE pp_15 PARTITION OF pp_1 FOR VALUES FROM (1) TO (5);
 CREATE TABLE pp_510 PARTITION OF pp_2 FOR VALUES FROM (5) TO (10);
-
 INSERT INTO pp SELECT g, 10 + g FROM generate_series(1,6) g;
-
 COPY pp TO stdout(header);
 DROP TABLE PP;