CHAR (Transact-SQL)

• 10/19/2018
• 3 minutes to read
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APPLIES TO: SQL Server Azure SQL Database Azure Synapse Analytics (SQL DW) Parallel Data Warehouse

This function converts an int ASCII code to a character value.

Transact-SQL Syntax Conventions

Syntax

CHAR ( integer_expression )  

Arguments

integer_expression
An integer from 0 through 255. CHAR returns a NULL value for integer expressions outside this range, or when then integer expresses only the first byte of a double-byte character.

Return types

char(1)

Remarks

Use CHAR to insert control characters into character strings. This table shows some frequently used control characters.

Examples

A. Using ASCII and CHAR to print ASCII values from a string

This example prints the ASCII value and character for each character in the string New Moon.

SET TEXTSIZE 0;  
-- Create variables for the character string and for the current   
-- position in the string.  
DECLARE @position int, @string char(8);  
-- Initialize the current position and the string variables.  
SET @position = 1;  
SET @string = 'New Moon';  
WHILE @position <= DATALENGTH(@string)  
   BEGIN  
   SELECT ASCII(SUBSTRING(@string, @position, 1)),   
      CHAR(ASCII(SUBSTRING(@string, @position, 1)))  
   SET @position = @position + 1  
   END;  
GO  

Here is the result set.

----------- -
78          N  
----------- -  
101         e  
----------- -  
119         w  
----------- -  
32  
----------- -  
77          M  
----------- -  
111         o  
----------- -  
111         o  
----------- - 
110         n  

B. Using CHAR to insert a control character

This example uses CHAR(13) to print the name and e-mail address of an employee on separate lines, when the query returns its results as text. This example uses the AdventureWorks2012 database.

SELECT p.FirstName + ' ' + p.LastName, + CHAR(13)  + pe.EmailAddress   
FROM Person.Person p 
INNER JOIN Person.EmailAddress pe ON p.BusinessEntityID = pe.BusinessEntityID  
  AND p.BusinessEntityID = 1;  
GO  

Here is the result set.

Ken Sanchez
ken0@adventure-works.com
  
(1 row(s) affected)

C. Using ASCII and CHAR to print ASCII values from a string

This example assumes an ASCII character set. It returns the character value for six different ASCII character number values.

SELECT CHAR(65) AS [65], CHAR(66) AS [66],   
CHAR(97) AS [97], CHAR(98) AS [98],   
CHAR(49) AS [49], CHAR(50) AS [50];  

Here is the result set.

65   66   97   98   49   50  
---- ---- ---- ---- ---- ----  
A    B    a    b    1    2  

D. Using CHAR to insert a control character

This example uses CHAR(13) to return information from sys.databases on separate lines, when the query returns its results as text.

SELECT name, 'was created on ', create_date, CHAR(13), name, 'is currently ', state_desc   
FROM sys.databases;  
GO  

Here is the result set.

name                                      create_date               name                                  state_desc  
--------------------------------------------------------------------------------------------------------------------  
master                    was created on  2003-04-08 09:13:36.390   master                  is currently  ONLINE 
tempdb                    was created on  2014-01-10 17:24:24.023   tempdb                  is currently  ONLINE   
AdventureWorksPDW2012     was created on  2014-05-07 09:05:07.083   AdventureWorksPDW2012   is currently  ONLINE 

E. Using CHAR to return single-byte characters

This example uses the integer and hex values in the valid range for ASCII. The CHAR function is able to output the single-byte Japanese character.

SELECT CHAR(188) AS single_byte_representing_complete_character, 
  CHAR(0xBC) AS single_byte_representing_complete_character;  
GO  

Here is the result set.

single_byte_representing_complete_character single_byte_representing_complete_character
------------------------------------------- -------------------------------------------
ｼ                                           ｼ                                         

F. Using CHAR to return multibyte characters

This example uses the an integer and hex values in the valid range for ASCII. However, the CHAR function returns NULL because the parameter represents only the first byte of a multibyte character.

SELECT CHAR(129) AS first_byte_of_double_byte_character, 
  CHAR(0x81) AS first_byte_of_double_byte_character;  
GO  

Here is the result set.

first_byte_of_double_byte_character first_byte_of_double_byte_character
----------------------------------- -----------------------------------
NULL                                NULL                                         

See also

ASCII (Transact-SQL)
NCHAR (Transact-SQL)
UNICODE (Transact-SQL)
+ (String Concatenation) (Transact-SQL)
String Functions (Transact-SQL)