SQLSaturday #620 - Dublin 2017

Although we won’t be presenting any Immersion Events in Europe in 2017, Kimberly and I will both be presenting workshops and sessions at SQLSaturday Dublin in June – our first SQLSaturday ever!

 

My workshop details:

  • Performance Troubleshooting Using Waits and Latches
  • One of the first things you should check when investigating performance issues are wait and latch statistics, as these can often point you in the right direction for further analysis. Unfortunately many people misinterpret what SQL Server is telling them and jump to conclusions about how to solve the problem – what is often called ‘knee-jerk performance tuning’.
    In this full-day workshop, you’ll learn how to investigate and interpret wait and latch statistics – practical techniques you can take home and start using immediately. You’ll also learn what a myriad of wait and latch types actually mean and how you can investigate lightly-documented types to gain insight into what causes them. Don’t waste time when it comes to performance troubleshooting; wait statistics are the fastest route to understanding your problems and this workshop will help you get there faster.
  • Thursday, June 15th
  • Eventbrite registration link

Kimberly’s workshop details:

  • Queries Gone Wrong: Statistics, Cardinality, Solutions
  • Have you ever wondered why SQL Server did what it did when processing your query? Have you wondered if it could have done better? Query estimates/statistics are often at the key to understanding; this session will explain the what, why, and how about estimates!
    Most of the time SQL Server returns data quickly – except when it doesn’t. Ultimately, what you see in the plan, just doesn’t seem to make sense. Why? Where did it come up with this plan? From one side, Transact-SQL is a declarative language that details what data you need but without information about how SQL Server should get it. Join order, predicate analysis – this is what SQL Server has to decide based on your query’s input? But, what should be processed first? Which table should we use to “drive” the join? Usually, it’s the table with the smallest number of rows that match your query’s predicates. But, how do they know which has the smallest set before they process the data? Statistics!
    There are numerous reasons why query performance can suffer and in this full-day workshop, Kimberly will cover a number of critical areas and for each – show you the behaviors, execution plans, troubleshooting techniques, and most importantly, possible solutions. This full-day workshop is about solving your query performance problems. Each problem has a different way of approaching it and you’ll walk away with a plethora of strategies to troubleshoot and tackle even gnarly query problems. Stop with the “sledgehammer” approaches (updating statistics, rebuilding indexes, recompiling plans, clearing cache, restarting SQL Server) and solve the problem. In this full-day workshop, you’ll learn much more finessed ways to solve query plan quality problems.
    Topics covered include understanding / maintaining statistics, handing VLTs / skewed data, distribution problems, troubleshooting common and advanced scenarios, and how to best utilize the cardinality estimation models (and trace flags) available in SQL Server versions 2008-2016.
  • Friday, June 16th
  • Eventbrite registration link

My Saturday session details:

  • Advanced Data Recovery Techniques
  • Disasters happen – plain and simple. When disaster strikes a database you’re responsible for, and backups and repair fail, how can you salvage data, and possibly your company and your job? This is where advanced data recovery techniques come in. Using undocumented tools and deep knowledge of database structures, you can manually patch up the database enough to extract critical data. This demo-heavy session will show you never-seen-before methods I’ve used extensively in the last year to salvage data for real-life clients after catastrophic corruption. You won’t believe what it’s possible to do!

Kimberly’s Saturday session details:

  • Plan Cache Pollution: Dealing with Ad Hoc Madness
  • How you execute your data requests can have a profound effect on performance and plan reuse. Did you ever wonder where that estimate (in the showplan) comes from? Is it correct or, is it way off? Why? You’ve probably heard that many of your problems are related to statistics. Potentially, you’ve even rebuilt statistics only to find that it fixes the problem. However, what you might be seeing is a false positive. And, it doesn’t always work. Come to this session to find out how you should be executing your statements for the best performance, caching, and reuse! We’ll look at ad hoc statements, dynamically constructed statements, and sp_executesql (e.g. forced statement caching) and I’ll debunk the mysteries around estimates so that you can solve performance problems the RIGHT way! If you want to demystify SQL Server’s decisions used for statement execution, query plans, and plan caching – this is the place to be!

The link to the main SQLSaturday Dublin web page is here.

There are a ton of excellent speakers attending from around the world, so it’s going to be a really great weekend – we hope to see you there!