PostgreSQL check constraint for foreign key condition

Question

I have a table of users eg:

create table \"user\" (
    id serial primary key,
    name text not null,
    superuser boolean not null default false
);
         


        

Answer 1

Create a separate superuser table that inherits from the user table:

CREATE TABLE "user" (
    id serial PRIMARY KEY,
    name text NOT NULL,
);

CREATE TABLE superuser () INHERITS ("user");

The user_has_job table can then reference the superuser table:

CREATE TABLE user_has_job (
    user_id integer REFERENCES superuser (id),
    job_id integer REFERENCES job(id),
    PRIMARY KEY (user_id, job_id)
);

Move users around between the tables as needed by inserting and deleting:

WITH promoted_user AS (
    DELETE FROM "user" WHERE id = 1 RETURNING *
) INSERT INTO superuser (id, name) SELECT id, name FROM promoted_user;