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NULL (SSIS Expression)

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

Returns a null value of a requested data type.

Syntax

  
NULL(typespec)  

Arguments

typespec
Is a valid data type. For more information, see Integration Services Data Types.

Result Types

Any valid data type with a null value.

Remarks

NULL returns a null result if the argument is null.

Parameters are required to request a null value for some data types. The following table lists these data types and their parameters.

Data type Parameter Example
DT_STR charcount

codepage
(DT_STR,30,1252) casts 30 characters to the DT_STR data type using the 1252 code page.
DT_WSTR charcount (DT_WSTR,20) casts 20 characters to the DT_WSTR data type.
DT_BYTES bytecount (DT_BYTES,50) casts 50 bytes to the DT_BYTES data type.
DT_DECIMAL scale (DT_DECIMAL,2) casts a numeric value to the DT_DECIMAL data type using a scale of 2.
DT_NUMERIC precision

scale
(DT_NUMERIC,10,3) casts a numeric value to the DT_NUMERIC data type using a precision of 10 and a scale of 3.
DT_TEXT codepage (DT_TEXT,1252) casts a value to the DT_TEXT data type using the 1252 code page.

Expression Examples

These examples return the null value of the data types: DT_STR, DT_DATE, and DT_BOOL.

NULL(DT_STR,10,1252)  
NULL(DT_DATE)  
NULL(DT_BOOL)  

See Also

ISNULL (SSIS Expression)
Functions (SSIS Expression)