gistfile1.txt

#3 NOT ENFORCED -> ENFORCED resets pg_trigger tgdeferrable and tginitdeferred value to f

```
postgres=# select version();
                                                           version
-----------------------------------------------------------------------------------------------------------------------------
 PostgreSQL 18.3 (Homebrew) on aarch64-apple-darwin25.2.0, compiled by Apple clang version 17.0.0 (clang-1700.6.3.2), 64-bit
(1 row)
postgres=# CREATE TABLE parent (
    id INT PRIMARY KEY
);
CREATE TABLE
postgres=# CREATE TABLE child (
    id        INT PRIMARY KEY,
    parent_id INT,
    CONSTRAINT child_parent_fk
        FOREIGN KEY (parent_id)
        REFERENCES parent(id)
        DEFERRABLE INITIALLY DEFERRED
);
CREATE TABLE
postgres=# SELECT
    conname,
    condeferrable,
    condeferred
FROM pg_constraint
WHERE conname = 'child_parent_fk';
     conname     | condeferrable | condeferred
-----------------+---------------+-------------
 child_parent_fk | t             | t
(1 row)

postgres=# SELECT
    tgname,
    tgdeferrable,
    tginitdeferred
FROM pg_trigger
WHERE tgname LIKE 'RI_ConstraintTrigger%';
            tgname            | tgdeferrable | tginitdeferred
------------------------------+--------------+----------------
 RI_ConstraintTrigger_a_25888 | t            | t
 RI_ConstraintTrigger_a_25889 | t            | t
 RI_ConstraintTrigger_c_25890 | t            | t
 RI_ConstraintTrigger_c_25891 | t            | t
(4 rows)

postgres=# ALTER TABLE child ALTER CONSTRAINT child_parent_fk NOT ENFORCED;
ALTER TABLE
postgres=# ALTER TABLE child ALTER CONSTRAINT child_parent_fk ENFORCED;
ALTER TABLE
postgres=# SELECT
    conname,
    condeferrable,
    condeferred
FROM pg_constraint
WHERE conname = 'child_parent_fk';
     conname     | condeferrable | condeferred
-----------------+---------------+-------------
 child_parent_fk | t             | t
(1 row)

postgres=# SELECT
    tgname,
    tgdeferrable,
    tginitdeferred
FROM pg_trigger
WHERE tgname LIKE 'RI_ConstraintTrigger%';
            tgname            | tgdeferrable | tginitdeferred
------------------------------+--------------+----------------
 RI_ConstraintTrigger_a_25892 | f            | f
 RI_ConstraintTrigger_a_25893 | f            | f
 RI_ConstraintTrigger_c_25894 | f            | f
 RI_ConstraintTrigger_c_25895 | f            | f
(4 rows)

postgres=# BEGIN;
BEGIN
postgres=*# SET CONSTRAINTS child_parent_fk DEFERRED;
SET CONSTRAINTS
postgres=*# INSERT INTO child (id, parent_id) VALUES (1, 999);
ERROR:  insert or update on table "child" violates foreign key constraint "child_parent_fk"
DETAIL:  Key (parent_id)=(999) is not present in table "parent".
postgres=!#
```