In SQL Server, each column, local variable, expression, and parameter has a related data type. A data type is an attribute that specifies how the data is used (in the client layer) and how the data is stored behind the scenes in the form of Zeros and Ones (storage characteristics and storage format - in memory and on disk).

In many cases people confuse between these layers and speak about the "Data Storing format" while they mean "Data Displaying format" or vice versa. Another misconception is that the data in table is stored on the disk in the exact same format as the data on-the-fly (for example binary value in a column type DATETIME2 and a variable of Data type DATETIME2 are not exactly the same).

This session focuses on the internal layer of SQL servers. We will explore the "Data Storing format" of different Data Types, and we'll learn how SQL Server actually stores the data behind the scene (cover as many data types as the time will allow us).

This knowledge opens powerful options to improve performance by selecting the right best practice, deal with corrupted data, working with detached data files, and more.

Note! During the demo, we are going to show and use several undocumented tools from different versions of SQL Server. This is advance topic (level 500 internals)!