DATALENGTH (T-SQL)

Returns the number of bytes used to represent any expression.

Syntax

DATALENGTH(expression)

Arguments

expression

Is an expression of any type.

Return Types

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.

Examples

This example finds the length of the pub_name column in the publishers table.

USE pubs

GO

SELECT length = DATALENGTH(pub_name), pub_name

FROM publishers

ORDER BY pub_name

GO

Here is the result set:

length      pub_name                                

----------- ----------------------------------------

20          Algodata Infosystems                    

16          Binnet & Hardley                        

21          Five Lakes Publishing                   

5           GGG&G                                   

18          Lucerne Publishing                      

14          New Moon Books                          

17          Ramona Publishers                       

14          Scootney Books                          

(8 row(s) affected)

See Also