PostgreSQL "RETURNING"

Today I learned that PostgreSQL INSERT/UPDATE/DELETE has a RETURNING clause that returns the computed values.

We can use it to get values that are generated by database such as sequences or defaults.

Check this out:

DROP TABLE IF EXISTS users;

CREATE TABLE users (
  id    SERIAL PRIMARY KEY,
  email VARCHAR NOT NULL UNIQUE
);

INSERT INTO users (email) VALUES ('user1@example.com');
-- INSERT 0 1

INSERT INTO users (email) VALUES ('user2@example.com') RETURNING *;
--  id |       email
-- ----+-------------------
--   2 | user2@example.com
-- (1 row)

h/t @joshuadavey