Understanding Execution Plans

Did you ever wonder if there was a way to see what happens inside SQL Server when you submit a query? Did you want to know if your indexes are getting used? Have you been curious about how SQL Server does a join between two tables? Did you just need to understand why your query is running so slow? The answers to all these questions, and more, are contained within SQL Server execution plans. My goal will be to show you how to generate execution plans and how to read them after they’re generated. You’ll learn the difference between an estimated and an actual execution plan and when to use each one. You’ll discover how to read a graphical execution plan and follow your data through the plan as it gets joined to other tables or filtered by WHERE clauses or aggregate functions. After watching this session, you’ll understand how to get detailed information out of execution plans, what operators to watch for, how to tell if the right operator is being used for your data, and all the bits and pieces of different kinds of data that are immediately available inside SQL Server execution plans.

Understanding Execution Plans

Every DBA runs into this. You've got a query that's not doing what you want, or not doing it fast enough. What's going on inside it? Are the indexes being used? How are the tables being joined? WHY IS IT SO SLOW!?! The answers to all of these questions and more are found within SQL Server execution plans, which are a complete pain to read if you aren't familiar with them. This presentation will clarify when and how to read an execution plan. Most importantly, how to trace down query problems in them, and the detailed information needed to solve those problems.