While preparing for my SQL Saturday Salt Lake City presentation, Climbing the B-Tree, I ran into one of the “word of mouth” facts that the first column of an index should be highly selective, i.e., it should only point to one or a few rows. This is not always the case and I’ll show you […]
In Part 1 of this article we looked at a specific use case (probably exaggerated) that gave us an idea about how CPU and IO performance might be affected by a bad page split. We continue this analysis looking at what really happens to the data on the leaf pages of a clustered index with […]
Introduction Fill Factor is a parameter most of us have ignored because there is no definitive way to calculate what the correct value should be. Part 1 of this series describes a new technique to dynamically determine index fill factors for all indexes within a database. Part 2 covers an analysis of the data collection […]
Introduction So what’s all the fuss about Fill Factor? It is a SQL Server parameter I’ve ignored for 20+ years. The main reason was/is I’ve had no idea about what value to use. There is just no documented definitive guidance. Back in April at SQL Saturday #830 - Colorado Springs, I attended two sessions by […]
Scalar functions in Query Plans just don't always show the whole story!