Can a SQL trigger raise an event in C#?

[Guest]

Hello,

I'm using VS2003 and SQL 2000.

Is it possible for a SQL trigger to raise an event in my C# program?

Thx.
Andy Jacobs

 

[Robbe Morris [C# MVP]]

Why would you want to do this?

If you want events raised, something in your
C# app should trigger that, not the database.

SQL Server really doesn't have any knowledge
or the memory address to try and hook into
regarding your C# application.

Can you expand on why you would want the
database to trigger something in your app that
couldn't be triggered by the app itself?

 

[Gunnar Liljas]

Why would you want to do this?

Agreed. It's a kind of dependency that should be avoided, but I guess it
can be accomplished using Notification Services

http://www.microsoft.com/sql/technologies/notification/techinfo.mspx

/Gunnar

 

[ManniAT]

I agree to Robbe,

but if there is a need a lot of ways are possible.
The simpliest approach (from my point of view) would be a call to an extended stored procedure.
This enables you to run native code which means you can do all you want:
Start a process, communicate with a service (which in fact could be you C# application) and so on.

Another simple approach could be to write a log entry.
And in your C# app you use an event watcher checking for that entry.
This last approach seems the easiest - and you have less dependicies as with an extended stored procedure.
So your trigger can stay fast - and as an isolated task the C# app reacts to the event log entry.
If you don't have to finish your C# task while in the trigger this could avoid a lot of timing (and other related) problems.

HTH

Manfred