DATALENGTH function in SQL Server

The article will explore and show you how to use the DATALENGTH function in SQL Server to display the number of bytes used to represent an expression .

Describe

The DATALENGTH function in SQL Server returns the length of an expression, in bytes.

Syntax

To use the DATALENGTH function in SQL Server, we use the following syntax:

 DATALENGTH(bieu_thuc) 

Parameters :

1. bieu_thuc: data you want to display the length in bytes. If the expression is NULL, DATALENGTH returns NULL

Note :

1. The DATALENGTH function calculates both the preceding and the following spaces when calculating the length of an expression.
2. The DATALENGTH function will return NULL if the expression is NULL.
3. See also the LEN function to calculate the length of the string but does not include spaces.
4. DATALENGTH function can be used in later versions of SQL Server: SQL Server 2017, SQL Server 2016, SQL Server 2014, SQL Server 2012, SQL Server 2008 R2, SQL Server 2008, and SQL Server 2005.

For example

Take a look and explore some examples of DATALENGTH functions in SQL Server.

 SELECT DATALENGTH('TipsMake.com'); 
 Result: 15 
 
 SELECT DATALENGTH(' TipsMake.com '); 
 Result: 17 
 
 SELECT DATALENGTH(1234); 
 Result: 4 
 
 SELECT DATALENGTH('20-02-2019'); 
 Result: 10 
 
 SELECT DATALENGTH(' '); 
 Result: 1 
 
 SELECT DATALENGTH(''); 
 Result: 0 
 
 SELECT DATALENGTH(NULL); 
 Result: NULL 

Previous article: Operator '+' in SQL Server

Next lesson: LEFT function in SQL Server