Hi,

I have a DAL which is used in several different applications (Winforms GUI Client, Webbased Reporting tool for customers, Backend Service for several long-running operations like transcoding of audio/video files etc)

Now i am running into trouble when more then one of these is working on the same object at the same time.. For example:

Service starts encoding a file and thus changes status to "encoding", Winforms Gui does not see this change because the object is still in cache and winforms instance of the DAL does not know of any changes to this object..

I cannot evict / refresh these objects all the time since this would defeat the prupose ( and be a major performance issue) So i am trying to figure out how i could do this best ?

Should i set a sort of a "version" column on every row ? Is there a way to have a global cache where multiple instances of the same DAL on different machines can check the cache instead of each instance locally ?