Advice on moving to a multi tier Delphi architecture

Question

We have a relatively large application that is strongly tied into Firebird (stored procedures, views etc). We are now getting a lot of requests to support additional databases a

Answer 1

For multi-tier architecture I also recommend to check out message-oriented middleware.

With message-oriented middleware, cross-language and cross-platform application integration can be implemented using the peer-to-peer or the publish/subscribe communication model. Messaging systems are loosely coupled, asynchronous and reliable. For example, they are core components in Java(tm) application servers such as JBoss.

For Firebird, I recently wrote a blog article on replacing Firebird database events, their limitations and ways to replace them with message-broker based solutions (which are available as open source):

• Firebird Database Events and Message-oriented Middleware (part 1)
• Firebird Database Events and Message-oriented Middleware (part 2)

(disclaimer: I am a developer of Delphi and Free Pascal client libraries for open source message brokers).