title: Reporting in ES/DDD Microservices
body: <p>I am just starting out with ES/DDD and I have a question how one is supposed to do reporting in this architecture.  Lets take a typical example, where you have a Customer Aggregate, Order Aggregate, and Product Aggregate all independent.</p>
  
  <p>Now if i want to run a query across all 3 aggregates and/or services, but that data is each in a separate DB, maybe one is SQL, one is a MongoDB, and one something else. How is one supposed to design or be able to run a query that would require a join across these aggregates ? </p>