Postgres 12

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CREATE TABLE t1 (
  gid int,
  geom geometry(point,4326) DEFAULT 'POINT EMPTY',
  PRIMARY KEY (gid,geom)
);

INSERT INTO t1 VALUES (42,'SRID=4326;POINT(1 1)');

CREATE TABLE

INSERT 0 1

CREATE TABLE t2 (
  gid int PRIMARY KEY,
  t1_gid int,
  t1_geom geometry(point,4326),
  FOREIGN KEY (t1_gid,t1_geom) 
	REFERENCES t1 (gid,geom)
	ON UPDATE CASCADE
);

INSERT INTO t2 VALUES (0,42,'SRID=4326;POINT(1 1)');

CREATE TABLE

INSERT 0 1

SELECT gid,t1_gid,ST_AsText(t1_geom) FROM t2;

gid
t1_gid
st_astext

0
42
POINT(1 1)

SELECT 1

UPDATE t1 SET gid = 1
WHERE gid = 42;

UPDATE 1

SELECT gid,t1_gid,ST_AsText(t1_geom) FROM t2;

gid
t1_gid
st_astext

0
1
POINT(1 1)

SELECT 1