Category Archives: String Functions

TRIM function in Sql Server

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Many a times we come across a scenario where we get an input string with leading and/or trailing spaces. In such scenarios we would like to store it into the database by removing the leading and trailing spaces. But Microsoft doesn’t have a built-in TRIM function which can remove both leading and Trailing spaces.

Instead it has LTRIM function which can be used to remove leading blanks and RTRIM function which can be used to remove trailing spaces. Let us understand these functions with examples and then see how we can nest these two functions together as shown in the below examples to remove leading and trailing spaces.

LTRIM Function

LTRIM function removes the leading spaces from the input string

DECLARE @StringToTrim VARCHAR(100) = '    String to trim    '
SELECT @StringToTrim 'String To Trim', 
	  DATALENGTH(@StringToTrim) 'Length of the string',
	  LTRIM(@StringToTrim) 'String trimmed by LTRIM', 
	  DATALENGTH(LTRIM(@StringToTrim)) 'Length of LTRIM string'

RESULT:
ltrim-in-sql-server

From the above result we can see that the LTRIM function is removing only the leading spaces. That is it has removed only the leading 4 spaces and not the trailing 4 spaces.

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RTRIM Function

RTRIM function removes the trailing spaces from the input string

DECLARE @StringToTrim VARCHAR(100) = '    String to trim    '
SELECT @StringToTrim 'String To Trim', 
	  DATALENGTH(@StringToTrim) 'Length of the string',
	  RTRIM(@StringToTrim) 'String trimmed by RTRIM', 
	  DATALENGTH(RTRIM(@StringToTrim)) 'Length of RTRIM string'

RESULT:
rtrim-in-sql-server

From the above result we can see that the RTRIM function is removing only the trailing spaces. That is it has removed only the trailing 4 spaces and not the leading 4 spaces.

[ALSO READ] Usage of Function on Index Column in WHERE Caluse Leads to Index/Table Scan

TRIM Function

To remove the leading and trailing spaces we can nest the above LTRIM and RTRIM functions as shown in the below example:

DECLARE @StringToTrim VARCHAR(100) = '    String to trim    '
SELECT @StringToTrim 'String To Trim', 
 DATALENGTH(@StringToTrim) 'Length of the string',
 RTRIM(LTRIM(@StringToTrim)) 'String trimmed by LTRIM and RTRIM', 
 DATALENGTH(RTRIM(LTRIM(@StringToTrim)))
  AS 'Length of trimmed string'

RESULT:
trim-in-sql-server

From the above result we can see that the nested use of RTRIM and LTRIM functions has removed both the leading and trailing paces.. That is it has removed both the leading 4 spaces and the trailing 4 spaces from the input string.

We can create a user defined function like the below one. And use it wherever we want to remove both leading and trailing spaces.

CREATE	FUNCTION dbo.TRIM(@StringToTrim VARCHAR(MAX))
RETURNS	VARCHAR(MAX)
BEGIN 
	RETURN	RTRIM(LTRIM(@StringToTrim))
END

Below example shows how we can use the above created user defined TRIM function:

DECLARE @StringToTrim VARCHAR(100) = '    String to trim    '
SELECT dbo.TRIM( @StringToTrim ) 'Trimmed string',
 DATALENGTH(dbo.TRIM( @StringToTrim )) 
  AS 'Length of trimmed string'

RESULT:
trim-function-in-sql-server

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FORMAT STRING FUNCTION IN SQL SERVER 2012

Functions, Sql Server, Sql Server 2012, String Functions, , , ,

FORMAT is one of the new built-in String Function introduced as a Part of Sql Server 2012. It returns the value formatted in the specified format using the optional culture parameter value. It is not an Sql Server native function instead it is .NET CLR dependent function.

SYNTAX: FORMAT ( value, format [, culture ] )

Parameter Description
value: Value to be formatted
format: This parameter specifies the format in which the vlaue will be formatted.
culture: This parameter is optional, it specifies the culture in which the value is formatted. If it is not specified then the language of the current session is used.

RETURNS: Return value type is nvarchar.

Example 1: FORMAT DATE with Culture

DECLARE @date DATETIME = GETDATE() 
SELECT @date AS 'GETDATE()',
       FORMAT( @date, 'd', 'en-US') AS 'DATE IN US Culture',
       FORMAT( @date, 'd', 'en-IN') AS 'DATE IN INDIAN Culture',
       FORMAT( @date, 'd', 'de-DE') AS 'DATE IN GERMAN Culture'

Result:

FORMAT_FUNCTION_IN_SQL_SERVER_2012_1

Example 2: FORMAT CURRENCY with Culture

DECLARE @Price INT = 40
SELECT FORMAT(@Price,'c','en-US') 
         AS 'CURRENCY IN US Culture',       
    FORMAT(@Price,'c','de-DE')
         AS 'CURRENCY IN GERMAN Culture'

Result:

FORMAT_FUNCTION_IN_SQL_SERVER_2012_2

Example 3: FORMAT CURRENCY

DECLARE @Price DECIMAL(5,3) = 40.356
SELECT FORMAT( @Price, 'C') AS 'Default',
      FORMAT( @Price, 'C0') AS 'With 0 Decimal',
       FORMAT( @Price, 'C1') AS 'With 1 Decimal',
       FORMAT( @Price, 'C2') AS 'With 2 Decimal',
       FORMAT( @Price, 'C3') AS 'With 3 Decimal'

Result:
FORMAT_FUNCTION_IN_SQL_SERVER_2012_3

Example 4: FORMAT PERCENTAGE

DECLARE @Percentage float = 0.35674
SELECT FORMAT( @Percentage, 'P') AS '% Default',
       FORMAT( @Percentage, 'P0') AS '% With 0 Decimal',
       FORMAT( @Percentage, 'P1') AS '% with 1 Decimal',
       FORMAT( @Percentage, 'P2') AS '% with 2 Decimal',
       FORMAT( @Percentage, 'P3') AS '% with 3 Decimal'

Result:
FORMAT_FUNCTION_IN_SQL_SERVER_2012_4

Example 5: FORMAT NUMBER

DECLARE @Number AS DECIMAL(10,2) = 454545.389
SELECT FORMAT( @Number, 'N','en-US') AS 'Number Format in US',
    FORMAT( @Number, 'N','en-IN')  AS 'Number Format in INDIA'

SELECT FORMAT( @Number, '#.0')     AS 'With 1 Decimal',
    FORMAT( @Number, '#.00')    AS 'With 2 Decimal',
    FORMAT( @Number, '#,##.00') AS 'With Comma and 2 Decimal',
    FORMAT( @Number, '##.00')   AS 'Without Comma and 2 Decimal'

Result:
FORMAT_FUNCTION_IN_SQL_SERVER_2012_5

Example 6: CUSTOM DATE FORMATS

DECLARE @date DATETIME = GETDATE() 
SELECT @date AS 'GETDATE()',
    FORMAT ( @date, 'dd/MM/yyyy') AS 'dd/MM/yyyy',
    FORMAT ( @date, 'MM/dd/yyyy') AS 'MM/dd/yyyy',
    FORMAT ( @date, 'yyyy/MM/dd') AS 'yyyy/MM/dd' 

SELECT 
 FORMAT( @date,'dddd, MMMM dd, yyyy hh:mm:ss tt','en-US')
   AS 'US',
 FORMAT( @date,'dddd, MMMM dd, yyyy hh:mm:ss tt','hi-IN')
   AS 'Hindi',
 FORMAT( @date,'dddd, MMMM dd, yyyy hh:mm:ss tt','kn-IN')
  AS 'Kannada'

Result:

FORMAT_FUNCTION_IN_SQL_SERVER_2012_6

DECLARE @date DATETIME = GETDATE()
SELECT FORMAT ( @date, 'dd', 'en-US' ) AS 'US',
	FORMAT ( @date, 'ddd', 'en-US' )   AS 'US',
	FORMAT ( @date, 'dddd', 'en-US' )  AS 'US',
	FORMAT ( @date, 'dddd', 'kn-IN' )  AS 'Kannada',
	FORMAT ( @date, 'dddd', 'hi-IN' )  AS 'Hindi'

SELECT FORMAT ( @date, 'M', 'en-US' )  AS 'US',
	FORMAT ( @date, 'MM', 'en-US' )    AS 'US',
	FORMAT ( @date, 'MMM', 'en-US' )   AS 'US',
	FORMAT ( @date, 'MMMM', 'en-US' )  AS 'US',
	FORMAT ( @date, 'MMMM', 'kn-IN' )  AS 'Kannada',
	FORMAT ( @date, 'MMMM', 'hi-IN' )  AS 'Hindi'

SELECT FORMAT ( @date, 'y', 'en-US' )   AS 'US',
       FORMAT ( @date, 'y', 'kn-IN' )   AS 'Kannada',
       FORMAT ( @date, 'y', 'hi-IN' )   AS 'Hindi',
       FORMAT ( @date, 'yy', 'en-US' )  AS 'US',
       FORMAT ( @date, 'yyy', 'en-US' ) AS 'US'

Result:

FORMAT_FUNCTION_IN_SQL_SERVER_2012_7

Example 7: Invalid Culture

DECLARE @date DATETIME = GETDATE()
SELECT FORMAT(@date,'d','Test') AS 'Invalid Culture'

Result:
Msg 9818, Level 16, State 1, Line 2
The culture parameter ‘Test’ provided in the function call is not supported.

You may like to read the below new built-in function’s introduced in Sql Server 2012:

New Built in Functions introduced in Sql Server
CONVERSION FUNCTIONS
PARSE TRY_PARSE
TRY_CONVERT
STRING FUNCTIONS
CONCAT FORMAT
LOGICAL FUNCTIONS
CHOOSE IIF
DATE AND TIME FUNCTIONS
EOMONTH
DATEFROMPARTS DATETIMEFROMPARTS
SMALLDATETIMEFROMPARTS DATETIME2FROMPARTS
TIMEFROMPARTS DATETIMEOFFSETFROMPARTS