Membership in PostgreSQL role


1IM 8.1

I created Native Database Connection (ADO.Net) for PostgreSQL DB. 

I created mappings UNSAccountB <-> pg_user view in PostgreSQL, UNSGroupB <-> pg_group view in PostgreSQL. 

Create and removing groups and users in PostgreSQL works correct.

If I want add user (pg_user) to group (pg_group) PostgreSQL I need run command GRANT pg_group_name TO  pg_user_name;

If I want del user (pg_user) from group (pg_group) PostgreSQL I need run command REVOKE pg_group_name FROM  pg_user_name;

I set DPRNameSpaceHasDialogTable.IsAdHocSingleMemberShip = TRUE for single Single Membership Provisioning. 

I don't understand how I can run the commands when needs add or delete user from group. 

Help, please.