two different databases - one application

[ignace]

Hello,

 

For a new project have I got the following situation:

 

A customer has an existing CMS system that grew over the years. Additional desktop programs where written to allow for easier, quicker editing (VB app that interfaces with the CMS db)

 

Problem: The customer asked us to write a new CMS system that fully integrated their workflow. So, only the CMS system is going to be replaced and thus the existing database structure can not be modified nor can it's data be copied as the VB apps would become obsolete (unless these would be updated to which is unlikely as the budget will not allow it)

 

Now I don't believe I need to write a new CMS from scratch as it's class structure allows for much flexibility and my current solution uses a Factory Method- and Façade pattern. Where the Façade contains all the database calls (not sure this is a good thing) and the Factory Method instantiates the appropriate Façade depending on the underlying database structure. The Façade itself would use the CMS specific models and take the necessary steps to retrieve the required data which is why I choose for the Façade pattern.

 

Do you know any better solution then this one?