title: What are the best SQL Server performance optimization techniques?
body: <p>I've always taken the approach of first deploying the database with a minimal set of indexes and then adding/changing indexes as performance dictates.</p>
  
  <p>This approach works reasonably well. However, it still doesn't tell me where I could improve performance. It only tells me where performance is so bad that users complain about it.</p>
  
  <p>Currently, I'm in the process of refactoring database objects on a lot of our applications. </p>
  
  <p>So should I not bother to look for performance improvements since "premature optimization is the root of all evil"? </p>
  
  <p>When refactoring application code, the developer is constantly looking for ways to improve the code quality. Is there a way to constantly be looking for improvements in database performance as well? If so, what tools and techniques have you found to be most helpful? </p>
  
  <p>I've briefly played around with the "Database engine tuning advisor" but didn't find it to be helpful at all. Maybe I just need more experience interpreting the results.</p>