A few days ago I received my attendee feedback from the SQLBits 2016 conference, which was held this time in lovely Liverpool. I had done a whole day precon about Locking, Blocking, and Deadlocking and a 1 hour long session about Joins in SQL Server. As easy as ABC? So let’s take a few minutes and reflect a little bit on the feedback.

Locking, Blocking, and Deadlocking

I love talking about this topic, because it consists of so many different concepts, which are very important when you work with concurrent users in a relational database. I always start this workshop by talking about the various Transaction Isolation Levels, and how they influence the concurrency of your workload. Based on that foundation I dig into more detail and talk about Locking itself, and how SQL Server uses it to isolate multiple concurrent users from each other, and how Blocking situations can be analyzed and finally troubleshot. A very large part of the day is also spent on Optimistic Concurrency, which is a miracle cure to solve a lot of different Blocking situations.

And finally I also cover Deadlocks! I always do this part with a very practical approach and simulate various kinds of Deadlocks, showing how you can analyze/understand them, and finally how to solve them. And the root cause of a Deadlock is very often a bad indexing strategy. The following picture shows the feedback score of my precon.

Not that bad! I have maxed almost everything out. I know that I can still improve in the area of my presentation skills. But that is mainly because English is not my mother language, and there are always some people who complain that I speak with an accent 😉 Here are some other feedback comments:

“Good evolution of the ideas from the basics to the more complex.”

“Really nice presentation with a lot of useful information. The demos were great and helped me understand better the information. Smiling always helps.”

“A clear, well presented and enjoyable session. Thanks.”

If you are interested in seeing this precon again, I will also be delivering it during the SQLSaturday Holland on October. You can find more information about that here.

Joins in SQL Server. As easy as ABC?

This new session from me was a gamble: I gave a basic introduction (Level 200) to Joins in SQL Server. I had done this session the first time last year at the SQLday conference in Wroclaw/Poland, where I had more than 80 people in the room. So I tried to do the same in the UK…

I started the session about talking about the logical Joins in SQL Server: Cross Joins, Inner Joins, and Left Joins. And based on that foundation I moved on to the physical execution in the form of the Nested Loop, the Merge Join, and the Hash Join operator. And at the end of this session I talked about more complex topics like the Semi Join and Anti Semi Join. So it’s really a basic introduction to Joins. Nothing more. The following picture shows again the feedback score.

It’s not that bad, but it seems that people had expected more from this session. But it was labeled as an 200 intro session. It seems that people only associate me with pure technical, complex stuff – good to know 😉 Here are also some comments:

“Presumed too basic but there were many take home points.”

“Very interesting! Sorry i had to leave early it was not through lack of interest.”

“Klaus is an excellent speaker who delivers very clear example.”

“Perfectionist. Knows his stuff!”

“Only draw back lecturer is too intelligent, needs to simplify his talk at times but he’s best so far for me.”

I don’t know how I should interprete the last comment, but I don’t think that I’m too intelligent. I just know my stuff, and love to speak about it – nothing more.

Thanks for your time,

-Klaus