java work

Messaging vs shared database

Martin Fowler's MultipleCanonicalModel entry hit the spot right on what's been happening around here lately.

His point is implementing conceptual models using shared databases in a large enterprise may not be a winning proposition whereas using message-based integration brings along all sorts of side gains.
I think the same point applies to B2B exchanges


The company I work for produces, provisions and distributes content to mobile devices. Up to now we've been delivering the provisionning of the content (ie what content is available in what node of the client's catalog) every couple weeks as a huge zip file containing data files and tables. The clients then update their sites' databases according to the tables. Basically a shared database strategy as far as I can tell, only it's across company boundaries.


We are currently moving towards a notification system based on messaging : everytime a use case that changes the content master repository is executed, a notification is fired and dispatched to wherever. This is a messaging based approach to integration which helps use decrease the time it takes to update our clients, is scalable and makes our lives easier.

It also somewhat shields our data model from what the client wants (he can probably have everything flat in his db if he wants). This is Fowler's 3rd point.
Our data model is actually richer than what most clients want, this is Fowler's 4th point.


How do you make a legacy system send notifications ? More to come...