I'm building an app that requires Data Integration with customer's database

Question

I'm in the process of designing an application that would tie into the database for multiple e-commerce stores.

I have the general business logic down but the problem is, I have no idea on the most painfree and effective way to do the data integration. I know how to access my own databases, but this is something I always just left to my hosting provider to handle the backend and I just developed the interface

Can someone point me in the right direction on this? There is a large emphasis on ease of installation. So my customers (once I get them) should be able to very easily integrate their system into my app.

Answer 1

RESTful web services are what many folks do for this.

Start here: http://en.wikipedia.org/wiki/Representational_State_Transfer

Then revise this to be a more specific question.

You might need to look at direct VPN/SSL connection from their server to yours.