Data Types and Advanced Data Types
Transact-SQL is a strongly-typed language. Columns and variables must have a valid data type, and the type is a constraint of the column. In this chapter, we will not cover all data types comprehensively. We will skip the obvious part and concentrate on specific information and on more complex and sophisticated data types that were introduced in SQL Server over time.
Basic Data Types
Basic data types like integer or varchar are pretty much self-explanatory. Some of these types have interesting and important-to-know properties or behavior, and even the most used, like varchar, are worth a look.