pg_auth_members
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 pg_auth_members Columns
| Column Type Description | 
|---|
 ID of a role that has a member  | 
 ID of a role that is a member of   | 
 ID of the role that granted this membership  | 
 True if   |