Postgres 13

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CREATE TABLE user_auth_custom (
  id serial,
  name VARCHAR ( 255 )
);

CREATE TABLE payment_action (
  id serial,
  user_auth_custom_id integer,
  message VARCHAR ( 255 )
);

CREATE TABLE work_action (
  id serial,
  user_auth_custom_id integer,
  message VARCHAR ( 255 )
);

INSERT INTO user_auth_custom VALUES
    (1, 'borris'),
    (2, 'jeremy'),
    (3, 'joe'),
    (4, 'barry');

INSERT INTO payment_action VALUES
    (1, 1, 'Paid $20'),
    (2, 1, 'Paid $340'),
    (3, 1, 'Paid $12'),
    (4, 2, 'Paid $120');
    
INSERT INTO work_action VALUES
    (1, 1, 'Submitted work abc'),
    (2, 1, 'did stuff'),
    (3, 1, 'more things'),
    (4, 1, 'loafing about'),
    (5, 1, 'dancing'),
    (6, 1, 'push ups'),
    (7, 1, 'monwalk'),
    (8, 2, 'balanced books'),
    (9, 2, 'read mind');
4 rows affected

4 rows affected

9 rows affected

SELECT t1.*
FROM user_auth_custom u
LEFT JOIN 
(
  SELECT user_auth_custom_id UserId,message,'Payment' ActionType
  FROM payment_action 
  UNION ALL
  SELECT user_auth_custom_id UserId,message,'Work'
  FROM work_action
) t1
ON u.id = t1.UserId
WHERE u.id = 1



userid
message
actiontype


1
Paid $20
Payment

1
Paid $340
Payment

1
Paid $12
Payment

1
Submitted work abc
Work

1
did stuff
Work

1
more things
Work

1
loafing about
Work

1
dancing
Work

1
push ups
Work

1
monwalk
Work


SELECT t1.*
FROM 
(
  SELECT user_auth_custom_id UserId,message,'Payment' ActionType
  FROM payment_action 
  UNION ALL
  SELECT user_auth_custom_id UserId,message,'Work'
  FROM work_action
) t1
WHERE UserId = 1



userid
message
actiontype


1
Paid $20
Payment

1
Paid $340
Payment

1
Paid $12
Payment

1
Submitted work abc
Work

1
did stuff
Work

1
more things
Work

1
loafing about
Work

1
dancing
Work

1
push ups
Work

1
monwalk
Work

userid	message	actiontype
1	Paid $20	Payment
1	Paid $340	Payment
1	Paid $12	Payment
1	Submitted work abc	Work
1	did stuff	Work
1	more things	Work
1	loafing about	Work
1	dancing	Work
1	push ups	Work
1	monwalk	Work