A Query Tuner’s Practical Guide to Statistics

Andy Yun

Have you ever heard that a huge difference in estimated vs actual number of rows can cause poor query performance? Ever wondered where SQL Server comes up with that “estimated number of rows” value in the first place?

The answer lies in SQL Server Statistics, which can be a very daunting if not dry subject matter. Come to this session for a practical guide to statistics for the T-SQL query writer and tuner. We will demystify statistics, the histogram, and how this impacts execution plan quality.

When you leave, you’ll have a strong understanding of the role statistics play in your execution plans, and how to dig deeper and tune those troublesome queries.