SQL Server Binary Data Types

Overview of SQL Server Binary Data Types

SQL Server provides several data types to store binary data: binary, varbinary, and image.

Each type has different storage characteristics and use cases.

• binary(n): Fixed-length binary data of n bytes (1 to 8000).
• varbinary(n): Variable-length binary data up to n bytes (1 to 8000).
• varbinary(max): Variable-length binary data up to 2 GB.
• image: Variable-length binary data up to 2 GB, deprecated in favor of varbinary(max).

Binary vs Varbinary Data Types

The binary data type stores fixed-length binary data. If the data is shorter than the specified length, it is padded with zeros.

The varbinary data type stores variable-length binary data without padding, making it more flexible for varying data sizes.

• Use binary when data size is consistent and fixed.
• Use varbinary when data size varies or can be large.
• Varbinary(max) supports very large binary objects like images or documents.

The Deprecated Image Data Type

The image data type was used in older versions of SQL Server to store large binary data up to 2 GB.

It is now deprecated and replaced by varbinary(max) which offers better functionality and compatibility.

• Avoid using image in new development.
• Migrate existing image columns to varbinary(max) if possible.

Storing and Retrieving Binary Data

Binary data can be inserted and retrieved using standard SQL commands with hexadecimal literals or parameters.

Applications often use parameters to pass binary data safely to SQL Server.

• Use hexadecimal notation like 0xFFAA for small binary literals.
• Use parameterized queries for inserting large binary data.
• Retrieve binary data as varbinary and process it in the application.

Example: Using varbinary in SQL Server

Here is a simple example showing how to create a table with a varbinary(max) column and insert binary data.