DATALENGTH (Transact-SQL)
Returns the number of bytes used to represent any expression.
Transact-SQL Syntax Conventions
Syntax
DATALENGTH ( expression )
Arguments
- expression
Is an expression of any data type.
Return Types
bigint if expression is of the varchar(max), nvarchar(max) or varbinary(max) data types; otherwise int.
Remarks
DATALENGTH is especially useful with varchar, varbinary, text, image, nvarchar, and ntext data types because these data types can store variable-length data.
The DATALENGTH of NULL is NULL.
Note
Compatibility levels can affect return values. For more information about compatibility levels, see sp_dbcmptlevel (Transact-SQL)
Examples
The following example finds the length of the Name
column in the Product
table.
USE AdventureWorks;
GO
SELECT length = DATALENGTH(Name), Name
FROM Production.Product
ORDER BY Name;
GO
See Also
Reference
LEN (Transact-SQL)
CAST and CONVERT (Transact-SQL)
Data Types (Transact-SQL)
System Functions (Transact-SQL)