Query grants for a table in postgres

Question

How can I query all GRANTS granted to an object in postgres?

For example I have table \"mytable\":

GRANT SELECT, INSERT ON mytable TO user1
GRANT UPD         


        

Answer 1

If you really want one line per user, you can group by grantee (require PG9+ for string_agg)

SELECT grantee, string_agg(privilege_type, ', ') AS privileges
FROM information_schema.role_table_grants 
WHERE table_name='mytable'   
GROUP BY grantee;

This should output something like :

 grantee |   privileges   
---------+----------------
 user1   | INSERT, SELECT
 user2   | UPDATE
(2 rows)