The catalog pg_auth_members shows the membership relations between roles. Any non-circular set of relationships is allowed.
Because user identities are cluster-wide, pg_auth_members is shared across all databases of a cluster: there is only one copy of pg_auth_members per cluster, not one per database.
Table 44-9. pg_auth_members Columns
| Name | Type | References | Description |
|---|---|---|---|
| roleid | oid | pg_authid.oid | ID of a role that has a member |
| member | oid | pg_authid.oid | ID of a role that is a member of roleid |
| grantor | oid | pg_authid.oid | ID of the role that granted this membership |
| admin_option | bool | True if member can grant membership in roleid to others |