Practical PostgreSQL

Granting Privileges

PostgreSQL maintains a tightly controlled set of access control lists or ACLs. This information describes which users are allowed to select from, update, and otherwise modify objects within a database. A set of access privileges and restrictions exist for each applicable database object in PostgreSQL (e.g., tables, views, and sequences). Superusers and owners of database objects maintain these ACLs through a pair of SQL commands: GRANT and REVOKE.

As stated in Chapter 9, when a user first creates a database, they are implicitly the owner of that database. Similarly, whenever someone creates that database object, it is owned by that individual who issued the related CREATE SQL command.

Aside from PostgreSQL superusers (who may manipulate any database object in any way), only the owners of database objects are allowed to grant and revoke privileges on the objects which they own. Though any user may connect to a database, if they wish access to objects within that database they must have those privileges explicitly granted to them.

Understanding Access Control

As mentioned earlier in this section, access control lists apply to three types of database objects: tables, lists, and sequences. For these objects, there are four general privileges which may be granted to, or revoked from, a user or group. The ability to revoke rights exists only to undo the function of having granted them. Users and groups have no rights to begin with.

From the psql client, you can view ACL ...