Converting Binary Data to Hexadecimal Strings in T-SQL: Two Easy Methods

1. fn_varbintohexstr: This function specifically converts varbinary(n) or binary(n) data types to a hexadecimal string.
2. CONVERT with base 16: This function offers more flexibility as it can convert various data types, including binary, to hexadecimal strings.

Here's a breakdown of each approach with examples:

Using fn_varbintohexstr:

This function directly takes the binary data as input and returns the corresponding hexadecimal string.

DECLARE @binaryData VARBINARY(5) = 0x0102030405;

SELECT fn_varbintohexstr(@binaryData) AS HexValue;

-- Output: 0102030405

Using CONVERT with base 16:

The CONVERT function allows you to specify the target base for conversion. In this case, we use base 16 for hexadecimal.

DECLARE @binaryData VARBINARY(5) = 0x0102030405;

SELECT CONVERT(CHAR(10), @binaryData, 16) AS HexValue;

-- Output: 0102030405

Explanation of the examples:

• We declare a variable @binaryData of type VARBINARY(5) to store a sample binary value.
• CONVERT: We convert the binary data to a CHAR(10) string with base 16, resulting in the hexadecimal representation.

Related Issues and Solutions:

• Empty binary data: Both functions return an empty string if the input binary data is empty.
• Fixed vs. variable length: fn_varbintohexstr is designed for variable-length binary data (VARBINARY(n)). If you have fixed-length binary data (BINARY(n)), you can either cast it to VARBINARY(n) before using the function or pad the binary data to ensure a consistent length.