22.5. Privilege Management Scenario #

Consider a scenario where privileges are granted based on a hierarchy from the main administrator to local administrators of user groups and analysts (refer to the diagram below).

Where:

  • Superuser is the Postgres Pro superuser with all privileges.

  • metastore_admin is the Postgres Pro AXE administrator.

  • Administrators A and B are local administrators of user groups that can access pgpro_metastore objects associated with these groups.

    Privileges are granted to administrators A and B by the Postgres Pro AXE administrator, and these administrators can grant privileges to analysts within each group.

  • Analysts A, B, C, and D are users that work with the OLAP data.

To configure this privilege management scenario:

  1. Create Postgres Pro roles on behalf of the superuser.

    Example 22.7. 

    postgres=# SELECT current_user;
    current_user
    --------------
    root
    postgres=# CREATE USER metastore_admin;
    postgres=# CREATE USER admin_a;
    postgres=# CREATE USER admin_b;
    postgres=# CREATE USER analyst_a;
    postgres=# CREATE USER analyst_b;
    postgres=# CREATE USER analyst_c;
    postgres=# CREATE USER analyst_d;
    

  2. Create schemas for user groups.

    Example 22.8. 

    postgres=# SELECT current_user;
    current_user
    --------------
    root
    postgres=# CREATE SCHEMA schema_a;
    postgres=# CREATE SCHEMA schema_b;
    

    Further scenario will be based on the schema_a schema. The steps for the schema_b schema are similar.

  3. Grant the metastore_admin and admin_a roles privileges on the schema_a schema.

    Example 22.9. 

    postgres=# SELECT current_user;
    current_user
    --------------
    root
    postgres=# GRANT ALL ON SCHEMA schema_a to metastore_admin WITH GRANT OPTION;
    postgres=# GRANT ALL ON SCHEMA schema_a to admin_a WITH GRANT OPTION;
    

  4. Grant the metastore_admin role privileges on the metastore schema and designate this role as the Postgres Pro AXE administrator:

    postgres=# SELECT current_user;
    current_user
    --------------
    root
    postgres=# GRANT ALL ON SCHEMA metastore TO metastore_admin;
    postgres=# ALTER SYSTEM SET duckdb.postgres_role TO 'metastore_admin';
    
  5. Restart the Postgres Pro server.

The Postgres Pro AXE administrator can now configure the metadata catalog.

Example 22.10. 

postgres=> SELECT current_user;
  current_user
-----------------
metastore_admin
postgres=> SELECT metastore.define_catalog_connection('localhost','5433','postgres', '', '');
postgres=> SELECT metastore.init();

If the group A has a heap table in its schema, and the OLAP data from this table must be used in Postgres Pro AXE for analytical queries:

  1. The Postgres Pro AXE administrator creates a storage and analytical table.

    Example 22.11. 

    postgres=> SELECT current_user;
      current_user
    -----------------
    metastore_admin
    postgres=> SELECT metastore.add_storage('mt_storage', 'file:///tmp/mt_storage/', 'file:///tmp/mt_storage/tmp_dir/');
    postgres=> SELECT metastore.add_table('mt_table1', 'mt_storage', 'schema_a.pg_table');
    

  2. The Postgres Pro AXE administrator grants the admin_a role the privilege on the analytical table.

    Example 22.12. 

      postgres=> SELECT current_user;
        current_user
      -----------------
      metastore_admin
      postgres=# SELECT metastore.mgrant('ALL','TABLE','mt_table1','admin_a', TRUE);
    

  3. The admin_a role can now copy the OLAP data from the heap table to the analytical table and create a Postgres Pro AXE view for this table.

    Example 22.13. 

      postgres=> SELECT current_user;
      current_user
      --------------
      admin_a
      postgres=> SELECT metastore.copy_table('mt_table1', 'select * from schema_a.pg_table');
      postgres=> SELECT metastore.create_view('mt_table1', 'schema_a');
    

  4. As owner of the analytical table, the Postgres Pro AXE administrator must allow the admin_a role to grant other roles the privilege.

    Example 22.14. 

      postgres=> SELECT current_user;
        current_user
      -----------------
      metastore_admin
      postgres=> GRANT SELECT ON schema_a.mt_table1 TO admin_a WITH GRANT OPTION;
    

  5. Now the admin_a role can grant other roles the privilege:

    Example 22.15. 

      postgres=> SELECT current_user;
      current_user
      --------------
      admin_a
      (1 row)
    
      postgres=> GRANT USAGE ON SCHEMA schema_a to analyst_a;
      postgres=> GRANT SELECT ON schema_a.mt_table1 TO analyst_a;
    

  6. Finally, the analyst_a role can execute the SELECT command on the analytical table.

      postgres=> SELECT current_user;
      current_user
      --------------
      analyst_a
      (1 row)
    
      postgres=> SELECT COUNT(*) FROM schema_a.mt_table1;
      count
      -------
          50
      (1 row)