Orb_fdw
This is a simple open-source data wrapper that bridges the gap between your Postgres database and Orb a leading usage-based billing solution.
Pre-requisistes
- have the v0.13.0 of 
orb_fdwextension enabled in your instance 
Create the foreign data wrapper:
create foreign data wrapper orb_wrapper
  handler orb_fdw_handler
  validator orb_fdw_validator;
Connect to orb using your credentials:
create server my_orb_server
  foreign data wrapper orb_wrapper
  options (
    api_key '<orb secret Key>')
Create Foreign Table:
Customers table
This table will store information about the users.
create foreign table orb_customers (
  user_id text,
  organization_id text,
  first_name text,
  email text,
  stripe_id text,
  created_at timestamp,
  attrs jsonb
  )
  server my_orb_server
  options (
      object 'customers'
  );
Subscriptions Table
This table will store information about the subscriptions.
create foreign table orb_subscriptions (
    subscription_id text,
    organization_id text,
    status text,
    plan text,
    started_date timestamp,
    end_date timestamp,
    attrs jsonb
  )
  server my_orb_server
  options (
    object 'subscriptions'
  );
Invoices Table
This table will store information about the subscriptions.
create foreign table orb_invoices (
    customer_id text,
    subscription_id text,
    organization_id text,
    status text,
    due_date timestamp,
    amount text,
    attrs jsonb
  )
  server my_orb_server
  options (
    object 'invoices'
  );