Guidance about developing a public application with lots of db's

[eluser]kevinprince[/eluser]
Hey Guys,

Im starting to develop a new version of an existing CRM project for multi company use. The current version is specific to the business I built it for, but there is large demand for a similar solution within the specific industry.

One of my main thoughts I have had is how to handle version migrations with databases. I want to stick each customer on there own database, so that there data is kept separate. This means when I rollout an update to the application, I need to be able to do it to lots of db's at the same time.

Hope this is clear any advice appreciated.