ASP.NET C# Webservice retrieve data and write to database every n seconds
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I'm trying to write a ASP.NET C# webservice that when running connects to an OPC Server (ignore the OPC part for now), retrieves a lot of data and then writes/inserts it into a SQL Database at a set interval.

My webapplication will then allow users to connect to the Database and see the live data that the webservice is continiously writing.

I'm completely new to webservices and I may have "missed the point" with them, but basically I need the service to run in the background and populate the database, so that all the different users can view the data live.

Any ideas on this? I'm completely lost.