Ensure that CREATE TABLE LIKE copies any NO INHERIT constraint property.

tglsfdc · tglsfdc · commit cacef172237f · 2020-03-10T14:54:00.000-04:00
Since the documentation about LIKE doesn't say that a copied constraint has properties different from the original, it seems that ignoring a NO INHERIT property doesn't meet the principle of least surprise. So make it copy that. (Note, however, that we still don't copy a NOT VALID property; CREATE TABLE offers no way to do that, plus it seems pointless.) Arguably this is a bug fix; but no back-patch, as it seems barely possible somebody is depending on the current behavior. Ildar Musin and Chris Travers; reviewed by Amit Langote and myself Discussion: https://postgr.es/m/CAONYFtMC6C+3AWCVp7Yd8H87Zn0GxG1_iQG6_bQKbaqYZY0=-g@mail.gmail.com
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
@@ -1133,12 +1133,14 @@ transformTableLikeClause(CreateStmtContext *cxt, TableLikeClause *table_like_cla
 	if ((table_like_clause->options & CREATE_TABLE_LIKE_CONSTRAINTS) &&
 		tupleDesc->constr)
 	{
+		TupleConstr *constr = tupleDesc->constr;
 		int			ccnum;
 
-		for (ccnum = 0; ccnum < tupleDesc->constr->num_check; ccnum++)
+		for (ccnum = 0; ccnum < constr->num_check; ccnum++)
 		{
-			char	   *ccname = tupleDesc->constr->check[ccnum].ccname;
-			char	   *ccbin = tupleDesc->constr->check[ccnum].ccbin;
+			char	   *ccname = constr->check[ccnum].ccname;
+			char	   *ccbin = constr->check[ccnum].ccbin;
+			bool		ccnoinherit = constr->check[ccnum].ccnoinherit;
 			Constraint *n = makeNode(Constraint);
 			Node	   *ccbin_node;
 			bool		found_whole_row;
@@ -1163,8 +1165,9 @@ transformTableLikeClause(CreateStmtContext *cxt, TableLikeClause *table_like_cla
 								   RelationGetRelationName(relation))));
 
 			n->contype = CONSTR_CHECK;
-			n->location = -1;
 			n->conname = pstrdup(ccname);
+			n->location = -1;
+			n->is_no_inherit = ccnoinherit;
 			n->raw_expr = NULL;
 			n->cooked_expr = nodeToString(ccbin_node);
 			cxt->ckconstraints = lappend(cxt->ckconstraints, n);
diff --git a/src/test/regress/expected/create_table_like.out b/src/test/regress/expected/create_table_like.out
@@ -388,6 +388,22 @@ ERROR:  column "a" has a storage parameter conflict
 DETAIL:  MAIN versus EXTENDED
 DROP TABLE ctlt1, ctlt2, ctlt3, ctlt4, ctlt12_storage, ctlt12_comments, ctlt1_inh, ctlt13_inh, ctlt13_like, ctlt_all, ctla, ctlb CASCADE;
 NOTICE:  drop cascades to table inhe
+-- LIKE must respect NO INHERIT property of constraints
+CREATE TABLE noinh_con_copy (a int CHECK (a > 0) NO INHERIT);
+CREATE TABLE noinh_con_copy1 (LIKE noinh_con_copy INCLUDING CONSTRAINTS);
+\d noinh_con_copy1
+          Table "public.noinh_con_copy1"
+ Column |  Type   | Collation | Nullable | Default 
+--------+---------+-----------+----------+---------
+ a      | integer |           |          | 
+Check constraints:
+    "noinh_con_copy_a_check" CHECK (a > 0) NO INHERIT
+
+-- fail, as partitioned tables don't allow NO INHERIT constraints
+CREATE TABLE noinh_con_copy1_parted (LIKE noinh_con_copy INCLUDING ALL)
+  PARTITION BY LIST (a);
+ERROR:  cannot add NO INHERIT constraint to partitioned table "noinh_con_copy1_parted"
+DROP TABLE noinh_con_copy, noinh_con_copy1;
 /* LIKE with other relation kinds */
 CREATE TABLE ctlt4 (a int, b text);
 CREATE SEQUENCE ctlseq1;
diff --git a/src/test/regress/sql/create_table_like.sql b/src/test/regress/sql/create_table_like.sql
@@ -151,6 +151,17 @@ CREATE TABLE inh_error2 (LIKE ctlt4 INCLUDING STORAGE) INHERITS (ctlt1);
 
 DROP TABLE ctlt1, ctlt2, ctlt3, ctlt4, ctlt12_storage, ctlt12_comments, ctlt1_inh, ctlt13_inh, ctlt13_like, ctlt_all, ctla, ctlb CASCADE;
 
+-- LIKE must respect NO INHERIT property of constraints
+CREATE TABLE noinh_con_copy (a int CHECK (a > 0) NO INHERIT);
+CREATE TABLE noinh_con_copy1 (LIKE noinh_con_copy INCLUDING CONSTRAINTS);
+\d noinh_con_copy1
+
+-- fail, as partitioned tables don't allow NO INHERIT constraints
+CREATE TABLE noinh_con_copy1_parted (LIKE noinh_con_copy INCLUDING ALL)
+  PARTITION BY LIST (a);
+
+DROP TABLE noinh_con_copy, noinh_con_copy1;
+
 
 /* LIKE with other relation kinds */
 
