Postgres 11

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CREATE TABLE parent
(
    parent_id bigint NOT NULL,
    name character varying(30) NOT NULL,
    email character varying(30) NOT NULL,
    child_id bigint NOT NULL,
    CONSTRAINT parent_pkey PRIMARY KEY (parent_id),
    CONSTRAINT unique_child UNIQUE (child_id)
);

CREATE TABLE child
(
    child bigint NOT NULL,
    money double precision NOT NULL,
    CONSTRAINT child_pkey PRIMARY KEY (child)
);

CREATE TABLE



CREATE TABLE


WITH insert_child AS (
    INSERT INTO child VALUES
    (42, 5.23)
    RETURNING child
)
INSERT INTO parent
SELECT 
    23,
    'Foo',
    'foo@bar.com',
    child
FROM insert_child;

INSERT 0 1


SELECT * FROM parent


parent_id
name
email
child_id


23
Foo
foo@bar.com
42



SELECT 1


SELECT * FROM child


child
money


42
5.23



SELECT 1