Sams Teach Yourself Transact-SQL in 21 Days, Second Edition

Understanding Large Data Types

Before we discuss large data types, let's take a brief look at the history of why they are useful. Prior to SQL Server Version 7.0, the largest character, text, or binary field allowable was 255 bytes. Of course, as applications became more sophisticated, this became a restriction. Since Version 7.0, the maximum size of these data types has expanded to 8,000 bytes. This was a large jump, but it is still a bit lacking for some application requirements. Many applications have the need to store more than 8,000 bytes of data. Some of the more common reasons are

• Long comments

• Detailed descriptions

• Resumes

• Digitized photographs or pictures

• Audio

• Video

These are only the most common uses for large data types (greater than 8,000 ...