T-SQL is a language that lets you formulate requests in a logical manner. By "logical," I mean that when you write a query, you specify what results you want but not how you want to get them. Devising how to process the query is the job of the query optimizer. Every problem you face that requires a T-SQL solution usually has many different solutions that eventually return the same result. In an ideal world, given two different queries that perform the same task, the optimizer would gener...