I'm thinking of using echo to handle the following scenario :
Xdata server containing product data and also sales data.
Clients pull the product data at regular intervals and push sales data when required.
Question 1 : When I add a new client (mobile app) it needs to sync the current product data. When the client is registered on the server, does the server create a change log with all current data as inserts, so that when the client pulls the data it will obtain the full product data, or does the client need to obtain the initial data via other means (eg normal Xdata request). If so when the client adds the data to its own local database does that not create updates in the change log which will eventually be pushed back to the server (which is not required).
Question 2 : When are change logs deleted in order to stop the database sizes becoming huge ?