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NULL (SSIS Expression)

Returns a null value of a requested data type.

Syntax

NULL(typespec)

Arguments

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.

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)