At the heart of SQL Server is the cost based optimizer.  Stop and think about that a minute, it attempts to give the “best plan” based on the cost of the work undertaken.  How does it know the cost of the work before its done the work ? This isn’t a conundrum, it doesn’t.  It estimates!  How does it estimate ? That is statistics.

This will be a deep dive into how the optimizer makes its decisions to give you a plan, the things that can go wrong and how you can have influence over these choices.

Presented by Dave Ballantyne at SQLBits XI
Slide Deck 2.3 MB
MP4 Video Low 101 MB
Demo Code 4 KB