diff --git a/src/backend/commands/sequence.c b/src/backend/commands/sequence.c
index 89122d4ad7..6d89925b23 100644
--- a/src/backend/commands/sequence.c
+++ b/src/backend/commands/sequence.c
@@ -172,7 +172,6 @@ DefineSequence(ParseState *pstate, CreateSeqStmt *seq)
 		coldef->is_local = true;
 		coldef->is_not_null = true;
 		coldef->is_from_type = false;
-		coldef->is_from_parent = false;
 		coldef->storage = 0;
 		coldef->raw_default = NULL;
 		coldef->cooked_default = NULL;
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 6048334c75..a0279ae383 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -1892,17 +1892,6 @@ MergeAttributes(List *schema, List *supers, char relpersistence,
 				 errmsg("tables can have at most %d columns",
 						MaxHeapAttributeNumber)));
 
-	/*
-	 * In case of a partition, there are no new column definitions, only dummy
-	 * ColumnDefs created for column constraints.  We merge them with the
-	 * constraints inherited from the parent.
-	 */
-	if (is_partition)
-	{
-		saved_schema = schema;
-		schema = NIL;
-	}
-
 	/*
 	 * Check for duplicate names in the explicit list of attributes.
 	 *
@@ -1916,17 +1905,19 @@ MergeAttributes(List *schema, List *supers, char relpersistence,
 		ListCell   *rest = lnext(entry);
 		ListCell   *prev = entry;
 
-		if (coldef->typeName == NULL)
-
+		if (!is_partition && coldef->typeName == NULL)
+		{
 			/*
 			 * Typed table column option that does not belong to a column from
 			 * the type.  This works because the columns from the type come
-			 * first in the list.
+			 * first in the list.  (We omit this check for partition column
+			 * lists; those are processed separately below.)
 			 */
 			ereport(ERROR,
 					(errcode(ERRCODE_UNDEFINED_COLUMN),
 					 errmsg("column \"%s\" does not exist",
 							coldef->colname)));
+		}
 
 		while (rest != NULL)
 		{
@@ -1959,6 +1950,17 @@ MergeAttributes(List *schema, List *supers, char relpersistence,
 		}
 	}
 
+	/*
+	 * In case of a partition, there are no new column definitions, only dummy
+	 * ColumnDefs created for column constraints.  Set them aside for now and
+	 * process them at the end.
+	 */
+	if (is_partition)
+	{
+		saved_schema = schema;
+		schema = NIL;
+	}
+
 	/*
 	 * Scan the parents left-to-right, and merge their attributes to form a
 	 * list of inherited attributes (inhSchema).  Also check to see if we need
@@ -2175,7 +2177,6 @@ MergeAttributes(List *schema, List *supers, char relpersistence,
 				def->is_local = false;
 				def->is_not_null = attribute->attnotnull;
 				def->is_from_type = false;
-				def->is_from_parent = true;
 				def->storage = attribute->attstorage;
 				def->raw_default = NULL;
 				def->cooked_default = NULL;
@@ -2428,59 +2429,51 @@ MergeAttributes(List *schema, List *supers, char relpersistence,
 	/*
 	 * Now that we have the column definition list for a partition, we can
 	 * check whether the columns referenced in the column constraint specs
-	 * actually exist.  Also, we merge the constraints into the corresponding
-	 * column definitions.
+	 * actually exist.  Also, we merge NOT NULL and defaults into each
+	 * corresponding column definition.
 	 */
-	if (is_partition && list_length(saved_schema) > 0)
+	if (is_partition)
 	{
-		schema = list_concat(schema, saved_schema);
-
-		foreach(entry, schema)
+		foreach(entry, saved_schema)
 		{
-			ColumnDef  *coldef = lfirst(entry);
-			ListCell   *rest = lnext(entry);
-			ListCell   *prev = entry;
+			ColumnDef  *restdef = lfirst(entry);
+			bool		found = false;
+			ListCell   *l;
 
-			/*
-			 * Partition column option that does not belong to a column from
-			 * the parent.  This works because the columns from the parent
-			 * come first in the list (see above).
-			 */
-			if (coldef->typeName == NULL)
-				ereport(ERROR,
-						(errcode(ERRCODE_UNDEFINED_COLUMN),
-						 errmsg("column \"%s\" does not exist",
-								coldef->colname)));
-			while (rest != NULL)
+			foreach(l, schema)
 			{
-				ColumnDef  *restdef = lfirst(rest);
-				ListCell   *next = lnext(rest); /* need to save it in case we
-												 * delete it */
+				ColumnDef  *coldef = lfirst(l);
 
 				if (strcmp(coldef->colname, restdef->colname) == 0)
 				{
+					found = true;
+					coldef->is_not_null |= restdef->is_not_null;
+
 					/*
-					 * merge the column options into the column from the
-					 * parent
+					 * Override the parent's default value for this column
+					 * (coldef->cooked_default) with the partition's local
+					 * definition (restdef->raw_default), if there's one. It
+					 * should be physically impossible to get a cooked default
+					 * in the local definition or a raw default in the
+					 * inherited definition, but make sure they're nulls, for
+					 * future-proofing.
 					 */
-					if (coldef->is_from_parent)
+					Assert(restdef->cooked_default == NULL);
+					Assert(coldef->raw_default == NULL);
+					if (restdef->raw_default)
 					{
-						coldef->is_not_null = restdef->is_not_null;
 						coldef->raw_default = restdef->raw_default;
-						coldef->cooked_default = restdef->cooked_default;
-						coldef->constraints = restdef->constraints;
-						coldef->is_from_parent = false;
-						list_delete_cell(schema, rest, prev);
+						coldef->cooked_default = NULL;
 					}
-					else
-						ereport(ERROR,
-								(errcode(ERRCODE_DUPLICATE_COLUMN),
-								 errmsg("column \"%s\" specified more than once",
-										coldef->colname)));
 				}
-				prev = rest;
-				rest = next;
 			}
+
+			/* complain for constraints on columns not in parent */
+			if (!found)
+				ereport(ERROR,
+						(errcode(ERRCODE_UNDEFINED_COLUMN),
+						 errmsg("column \"%s\" does not exist",
+								restdef->colname)));
 		}
 	}
 
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index e8ea59e34a..db49968409 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -2873,7 +2873,6 @@ _copyColumnDef(const ColumnDef *from)
 	COPY_SCALAR_FIELD(is_local);
 	COPY_SCALAR_FIELD(is_not_null);
 	COPY_SCALAR_FIELD(is_from_type);
-	COPY_SCALAR_FIELD(is_from_parent);
 	COPY_SCALAR_FIELD(storage);
 	COPY_NODE_FIELD(raw_default);
 	COPY_NODE_FIELD(cooked_default);
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index 3bb91c9595..3a084b4d1f 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -2553,7 +2553,6 @@ _equalColumnDef(const ColumnDef *a, const ColumnDef *b)
 	COMPARE_SCALAR_FIELD(is_local);
 	COMPARE_SCALAR_FIELD(is_not_null);
 	COMPARE_SCALAR_FIELD(is_from_type);
-	COMPARE_SCALAR_FIELD(is_from_parent);
 	COMPARE_SCALAR_FIELD(storage);
 	COMPARE_NODE_FIELD(raw_default);
 	COMPARE_NODE_FIELD(cooked_default);
diff --git a/src/backend/nodes/makefuncs.c b/src/backend/nodes/makefuncs.c
index 1bd2599c2c..4a2e669a86 100644
--- a/src/backend/nodes/makefuncs.c
+++ b/src/backend/nodes/makefuncs.c
@@ -496,7 +496,6 @@ makeColumnDef(const char *colname, Oid typeOid, int32 typmod, Oid collOid)
 	n->is_local = true;
 	n->is_not_null = false;
 	n->is_from_type = false;
-	n->is_from_parent = false;
 	n->storage = 0;
 	n->raw_default = NULL;
 	n->cooked_default = NULL;
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 69731ccdea..f0c396530d 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -2874,7 +2874,6 @@ _outColumnDef(StringInfo str, const ColumnDef *node)
 	WRITE_BOOL_FIELD(is_local);
 	WRITE_BOOL_FIELD(is_not_null);
 	WRITE_BOOL_FIELD(is_from_type);
-	WRITE_BOOL_FIELD(is_from_parent);
 	WRITE_CHAR_FIELD(storage);
 	WRITE_NODE_FIELD(raw_default);
 	WRITE_NODE_FIELD(cooked_default);
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 6d23bfb0b3..2effd51135 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -3388,7 +3388,6 @@ columnDef:	ColId Typename create_generic_options ColQualList
 					n->is_local = true;
 					n->is_not_null = false;
 					n->is_from_type = false;
-					n->is_from_parent = false;
 					n->storage = 0;
 					n->raw_default = NULL;
 					n->cooked_default = NULL;
@@ -3410,7 +3409,6 @@ columnOptions:	ColId ColQualList
 					n->is_local = true;
 					n->is_not_null = false;
 					n->is_from_type = false;
-					n->is_from_parent = false;
 					n->storage = 0;
 					n->raw_default = NULL;
 					n->cooked_default = NULL;
@@ -3429,7 +3427,6 @@ columnOptions:	ColId ColQualList
 					n->is_local = true;
 					n->is_not_null = false;
 					n->is_from_type = false;
-					n->is_from_parent = false;
 					n->storage = 0;
 					n->raw_default = NULL;
 					n->cooked_default = NULL;
@@ -12267,7 +12264,6 @@ TableFuncElement:	ColId Typename opt_collate_clause
 					n->is_local = true;
 					n->is_not_null = false;
 					n->is_from_type = false;
-					n->is_from_parent = false;
 					n->storage = 0;
 					n->raw_default = NULL;
 					n->cooked_default = NULL;
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index a6a2de94ea..2e222d822b 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -988,7 +988,6 @@ transformTableLikeClause(CreateStmtContext *cxt, TableLikeClause *table_like_cla
 		def->is_local = true;
 		def->is_not_null = attribute->attnotnull;
 		def->is_from_type = false;
-		def->is_from_parent = false;
 		def->storage = 0;
 		def->raw_default = NULL;
 		def->cooked_default = NULL;
@@ -1265,7 +1264,6 @@ transformOfType(CreateStmtContext *cxt, TypeName *ofTypename)
 		n->is_local = true;
 		n->is_not_null = false;
 		n->is_from_type = true;
-		n->is_from_parent = false;
 		n->storage = 0;
 		n->raw_default = NULL;
 		n->cooked_default = NULL;
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index aa4a0dba2a..9da8bf2f88 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -649,7 +649,6 @@ typedef struct ColumnDef
 	bool		is_local;		/* column has local (non-inherited) def'n */
 	bool		is_not_null;	/* NOT NULL constraint specified? */
 	bool		is_from_type;	/* column definition came from table type */
-	bool		is_from_parent; /* column def came from partition parent */
 	char		storage;		/* attstorage setting, or 0 for default */
 	Node	   *raw_default;	/* default value (untransformed parse tree) */
 	Node	   *cooked_default; /* default value (transformed expr tree) */
diff --git a/src/test/regress/expected/create_table.out b/src/test/regress/expected/create_table.out
index beb1acacc7..7b184330ed 100644
--- a/src/test/regress/expected/create_table.out
+++ b/src/test/regress/expected/create_table.out
@@ -728,6 +728,32 @@ LINE 1: ...TITION OF parted FOR VALUES IN ('c') PARTITION BY RANGE (c);
 CREATE TABLE part_c PARTITION OF parted (b WITH OPTIONS NOT NULL DEFAULT 0) FOR VALUES IN ('c') PARTITION BY RANGE ((b));
 -- create a level-2 partition
 CREATE TABLE part_c_1_10 PARTITION OF part_c FOR VALUES FROM (1) TO (10);
+-- check that NOT NULL and default value are inherited correctly
+create table parted_notnull_inh_test (a int default 1, b int not null default 0) partition by list (a);
+create table parted_notnull_inh_test1 partition of parted_notnull_inh_test (a not null, b default 1) for values in (1);
+insert into parted_notnull_inh_test (b) values (null);
+ERROR:  null value in column "b" violates not-null constraint
+DETAIL:  Failing row contains (1, null).
+-- note that while b's default is overriden, a's default is preserved
+\d parted_notnull_inh_test1
+      Table "public.parted_notnull_inh_test1"
+ Column |  Type   | Collation | Nullable | Default 
+--------+---------+-----------+----------+---------
+ a      | integer |           | not null | 1
+ b      | integer |           | not null | 1
+Partition of: parted_notnull_inh_test FOR VALUES IN (1)
+
+drop table parted_notnull_inh_test;
+-- check for a conflicting COLLATE clause
+create table parted_collate_must_match (a text collate "C", b text collate "C")
+  partition by range (a);
+-- on the partition key
+create table parted_collate_must_match1 partition of parted_collate_must_match
+  (a collate "POSIX") for values from ('a') to ('m');
+-- on another column
+create table parted_collate_must_match2 partition of parted_collate_must_match
+  (b collate "POSIX") for values from ('m') to ('z');
+drop table parted_collate_must_match;
 -- Partition bound in describe output
 \d+ part_b
                                    Table "public.part_b"
diff --git a/src/test/regress/sql/create_table.sql b/src/test/regress/sql/create_table.sql
index da301c8b68..2af4455ecf 100644
--- a/src/test/regress/sql/create_table.sql
+++ b/src/test/regress/sql/create_table.sql
@@ -654,6 +654,25 @@ CREATE TABLE part_c PARTITION OF parted (b WITH OPTIONS NOT NULL DEFAULT 0) FOR
 -- create a level-2 partition
 CREATE TABLE part_c_1_10 PARTITION OF part_c FOR VALUES FROM (1) TO (10);
 
+-- check that NOT NULL and default value are inherited correctly
+create table parted_notnull_inh_test (a int default 1, b int not null default 0) partition by list (a);
+create table parted_notnull_inh_test1 partition of parted_notnull_inh_test (a not null, b default 1) for values in (1);
+insert into parted_notnull_inh_test (b) values (null);
+-- note that while b's default is overriden, a's default is preserved
+\d parted_notnull_inh_test1
+drop table parted_notnull_inh_test;
+
+-- check for a conflicting COLLATE clause
+create table parted_collate_must_match (a text collate "C", b text collate "C")
+  partition by range (a);
+-- on the partition key
+create table parted_collate_must_match1 partition of parted_collate_must_match
+  (a collate "POSIX") for values from ('a') to ('m');
+-- on another column
+create table parted_collate_must_match2 partition of parted_collate_must_match
+  (b collate "POSIX") for values from ('m') to ('z');
+drop table parted_collate_must_match;
+
 -- Partition bound in describe output
 \d+ part_b