title: How do I add a record only if it doesn't already exist in SQL Server?
body: <p>I have a project in C# with a Sql-server Database.<br>
  In that database I have a table named 'Process' and columns named 'process_name', 'Full_Name' and 'Version' (all of the type:nvarchar(50)).<br>
  I want to write a query wich will add the new process, only if it doesn't exist in the table yet.<br>
  How can I do that?<br>
  Many thanks,</p>