Any way to notify clients of DB changes?

Does anyone know of a way to notify clients of database changes in real-time? The clients are non-web clients on a WAN. I would like to fire real-time events in clients when specific data changes. I do not want to implement any type of polling scheme in the clients. Any input would be greatly appreciated!

EverettDo you want the notification to go through an email or an actual pop-up on their machine ? Under what conditions would you be sending this ?|||Use triggers?|||The notifications would be sent when specified data changes. I can fire a trigger when the data is inserted/updated/deleted, but how can I get this to the clients? I want to fire an event in a VB application, as opposed to sending out an email. For this reason, SQL mail or notification services don't seem to be the right tools to use.

Everett|||Probably write a COM object and fire a method via a trigger. Look up sp_OACreate in the Books Online.
Either that or an xp_commandshell and write a command line prog to do the same thing.

I KNOW the above two would work... If you wanted to get fancy, , you could probably also implement it by having a SQL second connection with read uncommited isoaltion leve that doesn't time out and have the trigger insert to a table that all of the clients are doing a never ending select from. This solution seems interesting, but, is most likely untrodden territory.

Originally posted by Ev Conrad
The notifications would be sent when specified data changes. I can fire a trigger when the data is inserted/updated/deleted, but how can I get this to the clients? I want to fire an event in a VB application, as opposed to sending out an email. For this reason, SQL mail or notification services don't seem to be the right tools to use.

Everett