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LEFT (SSIS Expression)

Applies to: SQL Server SSIS Integration Runtime in Azure Data Factory

Returns the specified number of characters from the leftmost portion of the given character expression.

Syntax

  
LEFT(character_expression,number)  

Arguments

character_expression
Is a character expression from which to extract characters.

number
Is an integer expression that indicates the number of characters to be returned.

Result Types

DT_WSTR

Remarks

If number is greater than the length of character_expression, the function returns character_expression.

If number is zero, the function returns a zero-length string.

If number is a negative number, the function returns an error.

The number argument can take variables and columns.

LEFT works only with the DT_WSTR data type. A character_expression argument that is a string literal or a data column with the DT_STR data type is implicitly cast to the DT_WSTR data type before LEFT performs its operation. Other data types must be explicitly cast to the DT_WSTR data type. For more information, see Integration Services Data Types and Cast (SSIS Expression).

LEFT returns a null result if either argument is null.

Expression Examples

The following example uses a string literal. The return result is "Mountain".

LEFT("Mountain Bike", 8)  

See Also

RIGHT (SSIS Expression)
Functions (SSIS Expression)