Tables and relations structure

I am resting a demo now and trying to integrate CS-Cart and my in-store POS system. We will need to develop a method of importing our products database along with multiple images per product. Where can I get a description of the CS-Cart relational database, which will be needed to map our POS fields into CS-Cart and to automate import of multiple per product images?

What is the physical format of the data files on server? Can imports be made directly with SQL? Does CS-Cart automatically back up its database and could changes be rolled back if an import failed.

Is there a reference which explains what goes on under the hood? Since I am preparing our data for import into CS-Cart this is necessary knowledge, but the user reference guide was just an explanation of the admin interface.

Thanks for any insights.

Have you looked at the developer documentation?

If using v4, use the api.