Extending MFC Applications with the .NET Framework

Understanding Concurrency

The most challenging part of working with disconnected data is that each user is working with a snapshot of the data at the point that their respective dataset was filled. This is fine if you only have a handful of users who never work on the same data concurrently. However, in the real world, this isn't always the case. For example, let's take a standard distribution application where inventory can be updated by several modules. In our example, Bob works in receiving and has just received a shipment of four widgets. He pulls up the widget record, which shows a total of two units on hand. When he updates the record to the data store, it will reflect a total of six widgets on hand. However, before he clicks the Save button, ...