You can bind the "value" field you retrieve from SQL Server to the Value property of your desired gauge indicator.
We have attached a sample application that uses Linq To Sql Classes Template and WCF service to achieve the desired effect. The linq query is commented out and the sample emulates its result (Service1.GetScores method) but you can update the data context (DataClasses1.dbml) to use your actual table and then uncomment and change the query (you will also need to update the service reference).
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