I would like to share a specific integration use case.
Let's say that you have an investment management system and you want to send a daily activity summary email at the end of the day to your customers that had any activity during that day.
So what is the integration challenge? Well, how do you make sure that the email is updated?
You have 2 main alternatives (I have to tell you up front that my favorite is not No. 1):
1. Update all the customers details daily in a big batch. If you have as many customers as we keep, you would like to narrow the population to those that you need to update--e.g. those that will get the email. This method requires a service that can handle a lot of data-- probably not a web service.
2. Continuously update. Every time a customer page is opened in the investment management system, you call the CRM web service to update the specific customer details. This is done asynchronously in the background. At the end of the day, customers that had any activity in their account are updated with all the details and you just send the daily activity summary email.
--The service calls are single calls and are scattered nicely during the day. There's no need to worry about volume of data or heavy server activities.
--The population that is updated is exactly the population that you are interested in because it is the population that the users defined as interesting that day