Sparse Column Storage

What happens when we drop a column on a SQL Server table? Where's my space?

You have dropped a column and wondering why you haven't recovered any space? Let's take a look.

Identify Tables With Dropped Columns

How easily can we find tables with dropped columns that need cleanup?

Tempdb Pages

Understanding CRUD Operations on Tables with B-tree Indexes, Page-splits, and Fragmentation

Introduction Every DML transaction reads the data before it makes any changes. Not only during a SELECT query, but when you run any DML statement, insert, update, or delete, SQL Server first fetches a bunch of pages into the buffer pool locating the desired rows and changes them while synchronously writing to the transaction log […]

Understanding CRUD Operations Against Heaps and Forwarding Pointers

In this article, we examine how data changes are made against heaps.

Understanding the Internals of a Data Page

In Part 1 of this series, we examine the structure of data pages and how your tables are stored on these pages.

Heap Order

Transaction Log Structure

Intro This post shows the internal logical structure of the SQL Server Transaction Log. The details here target SQL Server 2000 to 2017. Note that SQL Server 2019 will...

The Mysterious Case of the Missing Default Value

Sometimes things are not exactly how we think they are. Read the story of the missing default value and learn why.