Microsoft® SQL Server® 2008 Internals

Change Tracking

Change Tracking is a feature designed to help eliminate the need for many of the custom synchronization schemes that developers must often create from scratch during an application’s lifetime. An example of this kind of system is when an application pulls data from the database into a local cache and occasionally asks the database whether any of the data has been updated, so that the data in the local store can be brought up to date. Most of these systems are implemented using triggers or timestamps, and they are often riddled with performance issues or subtle logic flaws. For example, schemes using timestamps often break down if the timestamp column is populated at insert time rather than at commit time. This can cause a problem ...