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A SQL Server, SQL Azure and Hekaton performance bench marking application that uses patterns.  Read more...

How does one get a truly random sample of data of a certain size from a SQL Server database table. Well, there are simple non-portable tricks one can use, such as the NewID() function, but then refining those can be tricky. Take the Rand() function for a start. Can it really provide you with a truly random number? Why doesn't the TABLESAMPLE clause give you a set number of rows? Joe Celko scratches his head a bit, explains some of the issues and invites some suggestions and tricks from readers.  Read more...

PASS Summit lands in Seattle from October 31 to November 3 this year, bringing with it the latest thinking and developments in the SQL Server world. This blog post from Annabel Bradford gives the details of what Redgate willl be presenting on, when this year's Redgate Rocks party will be, and how you can get involved with the team!  Read more...

By this stage, you should be familiar with the basics of SQL Server indexes. We've discussed what an Index actually is, as well as some of the most common types you're likely to encounter. Now that we've seen some simple examples of how Indexes can be useful, we're going to delve deeper into nonclustered indexes, as we'll see how they can improve the performance of more complex queries.  Read more...

When you can’t get to your data because another application has it locked, a thorough knowledge of SQL Server concurrency will give you the confidence to decide what to do.  Read more...

There is already a template on the Azure marketplace for setting up an AlwaysOn Availability Group. In just a few easy steps you can get a working AlwaysOn Availability Group setup, configured and running - this post describes the steps to quickly set it up.  Read more...

This article will give a brief overview of how statistics are generated, stored, and used in SQL Server.  Read more...

If you're attending the PASS Summit in 2017, there's a Freecon day on Tuesday you can attend.  Read more...

Erik figures out why SQL Server really doesn't like combining these two things in a query plan.  Read more...

I'm not a fan of R visuals in PowerBI. I recently learned I can use R to load data and native PowerBI visuals to display the data. Here's how.  Read more...

Unlike some other languages, T-SQL doesn’t have the concept of a constant. As good coders, we’ve all at some point tried...  Read more...

Temporal data storage, which was defined in the ANSI SQL:2011 standard, describes an architecture in which relational databases maintain row-level...  Read more...