I (finally) have a technical blog post:

In order to show you the solution, I want to build up a reasonable sized sample. Any solution looks great when reading five records, but let’s kick that up a notch. Or, more specifically, a million notches: I’m going to use a CTE tally table and load 5 million rows.

I want some realistic looking data, so I’ve adapted Dallas Snider’s strategy to build a data set which approximates a normal distribution.

Because this is a little complicated, I wanted to take the time and explain the data load process in detail in its own post, and then apply it in the follow-up post. We’ll start with a relatively small number of records for this demonstration: 50,000. The reason is that you can generate 50K records almost instantaneously but once you start getting a couple orders of magnitude larger, things slow down some.

If you do custom data generation for lower environments, I’d recommend checking this out. Your production data probably doesn’t follow a normal distribution exactly, but a normal distribution is probably closer to reality than the uniform distribution you get with functions like RAND().

Kevin Feasel

2019-01-03

Data, T-SQL, Testing