I have a need to implement a workflow for an application which checks a database value periodically and then invokes a relevant workflow to handle the state.

I can think of a couple of obvious ways of doing this:

1. Have a dedicated Thread which polls and determines when to fire a specific workflow.

2. Integrate this polling mechanism into the workflow design using a timer which is fired periodically. This would in turn execute an ActionHandler which would perform the database state check.

The main drawback with option 1 is that it isn't a unified approach to handling this types of workflow. If I need a new polling mechanism in the future, I will have to write a dedicated class.

Option 2 is promising, however, how dangerous is it to implement a polling mechanism in a workflow which effectively never ends?

All comments gratefully received,

Andy