Size of VARBINARY field in SQL Server 2005

sql

data-length

varbinary

sql-server

byAnton Shumikhin·Sep 17, 2024

A VARBINARY field in SQL Server 2005 is specified with a size n as in VARBINARY(n) for up to 8000 bytes, or VARBINARY(MAX) for up to 2 GB. Here’s a quick-start example of specifying a max-size VARBINARY column:

CREATE TABLE MyTable (
    MyColumn VARBINARY(MAX)
);

For optimal performance, replace MAX with the actual size required if the binary data is comparatively smaller.

T-SQL's Swiss Army Knife: DATALENGTH()

The robustness of T-SQL can be widely appreciated when it comes to determining byte size of a VARBINARY(MAX) field with a built-in function: DATALENGTH(). Here's how to use it:

-- Show me the bytes!
SELECT DATALENGTH(MyColumn) AS MyColumnSize
FROM MyTable

Right there, you have the byte size of your column's content without much hassle. Bye, CLR integration hassle!

Smoothly Handling NULLs

Oh, do you sometimes have NULL values in your VARBINARY field? T-SQL kindly takes care of that as well with ISNULL(). Combine it with DATALENGTH(), and you're ready to roll:

-- 0 bytes, instead of NULL. Null is not the answer to everything!
SELECT ISNULL(DATALENGTH(MyColumn), 0) AS MyColumnSize
FROM MyTable

This query ensures even rows with empty VARBINARY content don't cause inconsistency in your results.

The Space-Time-Complexity Continuum

In real-world applications, knowing the exact size of VARBINARY content is essential not just for storage optimization but for network efficiency and performance tuning as well. Furthermore, there are certain SQL Server features where the data size plays a crucial role.

Accurate Size Evaluation: Why it Matters

Indexing: Indexing strategies become efficient when you know the data size you're dealing with.
Replication: Avoid "Oops, it's too large!" issues during replication.
Memory Usage: Estimate the impact on the buffer pool and overall memory utilization.

Large Objects (LOB): Do's and Don'ts

Column Types: VARBINARY(MAX) is treated as a LOB data type, and SQL Server treats LOB storage a bit differently.
Performance Impact: Large VARBINARY fields might leave a footprint on your query performance.
Backup and Restore: Size does matter here - especially when it's all about the speed!

Experiments: Best way to Learn

Try running DATALENGTH() with different data sizes. This practical approach will ensure the function works reliably for all your requirements:

-- Null values. They deserve some love too!
SELECT ISNULL(DATALENGTH(MyColumn), 0) AS MyColumnSize
FROM MyTable

--  Life's all about variety!
SELECT TOP (10) DATALENGTH(MyColumn) AS MyColumnSize
FROM MyTable
ORDER BY DATALENGTH(MyColumn) DESC