I just discovered that trying to set a foreign key as NO INHERIT in
ALTER TABLE ALTER CONSTRAINT returns an absurd error message:
create table pk (a int primary key);
create table fk (a int references pk);
alter table fk alter constraint fk_a_fkey deferrable, alter constraint
fk_a_fkey no inherit;
ERROR: ALTER CONSTRAINT statement constraints cannot be marked NO INHERIT
The explanation is that somebody misunderstood what must be given to
processCASbits in 2013. The intended message is:
ERROR: FOREIGN KEY constraints cannot be marked NO INHERIT
Here's the fix along with some additional cleanup.
--
Álvaro Herrera Breisgau, Deutschland — https://www.EnterpriseDB.com/
>From ba95124d06e337c285a31b0376230702e6b1fc3d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=81lvaro=20Herrera?= <alvhe...@alvh.no-ip.org>
Date: Tue, 4 Mar 2025 18:48:14 +0100
Subject: [PATCH] Fix ALTER TABLE error message
This bogus error message was introduced in 2013 by commit f177cbfe676d,
because of misunderstanding the processCASbits() API; at the time, no
test cases were added that would be affected by this change. Only in
ca87c415e2fc was one added (along with a couple of typos), with an XXX
note that the error message was bogus. Fix the whole, add some test
cases.
Backpatch all the way back.
---
src/backend/parser/gram.y | 2 +-
src/test/regress/expected/constraints.out | 7 +++----
src/test/regress/expected/foreign_key.out | 10 +++++++++-
src/test/regress/sql/constraints.sql | 3 +--
src/test/regress/sql/foreign_key.sql | 4 +++-
5 files changed, 17 insertions(+), 9 deletions(-)
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 7d99c9355c6..c11a3beff06 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -2663,7 +2663,7 @@ alter_table_cmd:
n->def = (Node *) c;
c->conname = $3;
c->alterDeferrability = true;
- processCASbits($4, @4, "ALTER CONSTRAINT statement",
+ processCASbits($4, @4, "FOREIGN KEY",
&c->deferrable,
&c->initdeferred,
NULL, NULL, NULL, yyscanner);
diff --git a/src/test/regress/expected/constraints.out b/src/test/regress/expected/constraints.out
index 692a69fe457..4f39100fcdf 100644
--- a/src/test/regress/expected/constraints.out
+++ b/src/test/regress/expected/constraints.out
@@ -735,7 +735,7 @@ SELECT * FROM unique_tbl;
3 | threex
(5 rows)
--- enforcibility cannot be specified or set for unique constrain
+-- enforceability cannot be specified or set for unique constraint
CREATE TABLE UNIQUE_EN_TBL(i int UNIQUE ENFORCED);
ERROR: misplaced ENFORCED clause
LINE 1: CREATE TABLE UNIQUE_EN_TBL(i int UNIQUE ENFORCED);
@@ -744,13 +744,12 @@ CREATE TABLE UNIQUE_NOTEN_TBL(i int UNIQUE NOT ENFORCED);
ERROR: misplaced NOT ENFORCED clause
LINE 1: CREATE TABLE UNIQUE_NOTEN_TBL(i int UNIQUE NOT ENFORCED);
^
--- XXX: error message is misleading here
ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key ENFORCED;
-ERROR: ALTER CONSTRAINT statement constraints cannot be marked ENFORCED
+ERROR: FOREIGN KEY constraints cannot be marked ENFORCED
LINE 1: ...TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key ENFORCED;
^
ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key NOT ENFORCED;
-ERROR: ALTER CONSTRAINT statement constraints cannot be marked NOT ENFORCED
+ERROR: FOREIGN KEY constraints cannot be marked NOT ENFORCED
LINE 1: ...ABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key NOT ENFORC...
^
DROP TABLE unique_tbl;
diff --git a/src/test/regress/expected/foreign_key.out b/src/test/regress/expected/foreign_key.out
index 374dcb266e7..6a3374d5152 100644
--- a/src/test/regress/expected/foreign_key.out
+++ b/src/test/regress/expected/foreign_key.out
@@ -1278,11 +1278,19 @@ DETAIL: Key (fk)=(20) is not present in table "pktable".
COMMIT;
-- try additional syntax
ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT DEFERRABLE;
--- illegal option
+-- illegal options
ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT DEFERRABLE INITIALLY DEFERRED;
ERROR: constraint declared INITIALLY DEFERRED must be DEFERRABLE
LINE 1: ...e ALTER CONSTRAINT fktable_fk_fkey NOT DEFERRABLE INITIALLY ...
^
+ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NO INHERIT;
+ERROR: FOREIGN KEY constraints cannot be marked NO INHERIT
+LINE 1: ...ER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NO INHERIT...
+ ^
+ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT VALID;
+ERROR: FOREIGN KEY constraints cannot be marked NOT VALID
+LINE 1: ...ER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT VALID;
+ ^
-- test order of firing of FK triggers when several RI-induced changes need to
-- be made to the same row. This was broken by subtransaction-related
-- changes in 8.0.
diff --git a/src/test/regress/sql/constraints.sql b/src/test/regress/sql/constraints.sql
index d6742f83fb9..21ce4177de4 100644
--- a/src/test/regress/sql/constraints.sql
+++ b/src/test/regress/sql/constraints.sql
@@ -531,10 +531,9 @@ COMMIT;
SELECT * FROM unique_tbl;
--- enforcibility cannot be specified or set for unique constrain
+-- enforceability cannot be specified or set for unique constraint
CREATE TABLE UNIQUE_EN_TBL(i int UNIQUE ENFORCED);
CREATE TABLE UNIQUE_NOTEN_TBL(i int UNIQUE NOT ENFORCED);
--- XXX: error message is misleading here
ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key ENFORCED;
ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key NOT ENFORCED;
diff --git a/src/test/regress/sql/foreign_key.sql b/src/test/regress/sql/foreign_key.sql
index bc0adb8cfe9..44945b0453a 100644
--- a/src/test/regress/sql/foreign_key.sql
+++ b/src/test/regress/sql/foreign_key.sql
@@ -970,8 +970,10 @@ COMMIT;
-- try additional syntax
ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT DEFERRABLE;
--- illegal option
+-- illegal options
ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT DEFERRABLE INITIALLY DEFERRED;
+ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NO INHERIT;
+ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT VALID;
-- test order of firing of FK triggers when several RI-induced changes need to
-- be made to the same row. This was broken by subtransaction-related
--
2.39.5
