Postgres 12

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create table actors (
  id_act serial not null primary key,
  first_name text not null,
  last_name text not null
);
create table movies (
  id_mov serial not null primary key,
  act_id integer not null
);

CREATE TABLE

CREATE TABLE

INSERT INTO actors (first_name, last_name) VALUES ('Tom', 'Hanks');
INSERT INTO movies(act_id) values 
(currval(pg_get_serial_sequence('actors', 'id_act')));

INSERT 0 1

INSERT 0 1

    with new_actor as (
      INSERT INTO actors (first_name, last_name) VALUES ('Sean', 'Connery')
      returning id_act
    )
    insert into movies (act_id)
    select id_act
    from new_actor;

INSERT 0 1

select *
from actors;

id_act
first_name
last_name

1
Tom
Hanks

2
Sean
Connery

SELECT 2

select *
from movies

id_mov
act_id

1
1

2
2

SELECT 2