Postgres 12 | db<>fiddle

CREATE TABLE people ( id INT GENERATED ALWAYS AS IDENTITY, firstName VARCHAR(100), lastName VARCHAR(100), fullName VARCHAR(200) ); INSERT INTO people (firstName, lastName) VALUES ('firstName1', 'lastName1'), ('firstName2', 'lastName2'); SELECT * FROM people;

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2 rows affected

id	firstname	lastname
1	firstName1	lastName1
2	firstName2	lastName2
…

hidden batch(es)

ALTER TABLE people DROP COLUMN fullName, ADD COLUMN fullName VARCHAR(200) GENERATED ALWAYS AS (firstName || ' ' || lastName) STORED;

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hidden batch(es)

SELECT * FROM people; INSERT INTO people (firstName, lastName) VALUES ('firstName3', 'lastName3'); SELECT * FROM people; UPDATE people SET firstName = firstname || '_changed'; SELECT * FROM people;

id	firstname	lastname	fullname
1	firstName1	lastName1	firstName1 lastName1
2	firstName2	lastName2	firstName2 lastName2
…

1 rows affected

id	firstname	lastname	fullname
1	firstName1	lastName1	firstName1 lastName1
2	firstName2	lastName2	firstName2 lastName2
3	firstName3	lastName3	firstName3 lastName3
…

3 rows affected

id	firstname	lastname	fullname
1	firstName1_changed	lastName1	firstName1_changed lastName1
2	firstName2_changed	lastName2	firstName2_changed lastName2
3	firstName3_changed	lastName3	firstName3_changed lastName3
…

hidden batch(es)