BLANK DAX Function
Returns a blank.
Syntax
This expression has no parameters.
Return values
The BLANK value does not have a data type.
Remarks
The BLANK value is automatically converted in case it is compared with other values.
The right way to check whether a value is BLANK is by using either the operator == or the ISBLANK function. Do not use the operator “=”.
The operator == is a “strictly equal to” operator that consider BLANK as a different value other than 0 or an empty string.
See related articles for more details.
Examples
-- BLANK returns the BLANK value
--
-- It is mostly useful to blank out the result of a calculation
-- toor perform comparisons.
DEFINE
MEASURE Customer[EmptyNames] =
CALCULATE (
COUNTROWS ( Customer ),
Customer[Customer Name] == BLANK ()
)
EVALUATE
SUMMARIZECOLUMNS (
Customer[Continent],
"Customers", COUNTROWS ( Customer ),
"Customers with blank name", [EmptyNames]
)
| Continent | Customers | Customers with blank name |
|---|---|---|
| Asia | 3,658 | 34 |
| North America | 9,665 | 138 |
| Europe | 5,546 | 21 |
-- BLANK is useful also to provide BLANK arguments to some functions
-- like DATESBETWEEN.
EVALUATE
DATESBETWEEN (
'Date'[Date],
DATE ( 2011, 12, 20 ),
BLANK ()
)
ORDER BY 'Date'[Date]
| Date |
|---|
| 2011-12-20 |
| 2011-12-21 |
| 2011-12-22 |
| 2011-12-23 |
| 2011-12-24 |
| 2011-12-25 |
| 2011-12-26 |
| 2011-12-27 |
| 2011-12-28 |
| 2011-12-29 |
| 2011-12-30 |
| 2011-12-31 |
-- BLANK is equal to 0 and to an empty string in DAX.
-- You need to use == to check for "strictly equal to"
EVALUATE
{
( "Blank = 0", BLANK () = 0 ),
( "Blank = """"", BLANK () = "" ),
( "Blank == 0", BLANK () == 0 ),
( "Blank == """"", BLANK () == "" )
}
| Value1 | Value2 |
|---|---|
| Blank = 0 | true |
| Blank = “” | true |
| Blank == 0 | false |
| Blank == “” | false |
Related articles
Learn more about BLANK in the following articles:
-
How to handle BLANK in DAX measures
This article describes a counterintuitive behavior of BLANK in DAX measures affecting Power BI, Analysis Services, and Power Pivot. That behavior could cause mistakes in a report using alternate expressions of the same calculation. Indeed, these expressions are not equivalent when BLANK is involved. » Read more
-
Handling BLANK in DAX
The blank value in DAX is a special value requiring particular attention in comparisons. It is not like the special null value in SQL, and it could appear in any conversion from a table expression. This article explores in details the behavior of the blank value in DAX, highlighting a common error in DAX expressions […] » Read more
-
Blank row in DAX
There are two functions in DAX that return the list of values of a column: VALUES and DISTINCT. This article describes the difference between the two, explaining the details of the blank row added to tables for invalid relationships. » Read more
-
Optimizing conditions involving blank values in DAX
This article describes how blank values considered in a DAX conditional expression can affect its query plan and how to apply possible optimizations to improve performance in these cases. » Read more
-
From SQL to DAX: Implementing NULLIF and COALESCE in DAX
This article describes how to implement a syntax equivalent to the T-SQL function NULLIF and the ANSI SQL function COALESCE, in DAX. » Read more
Last update: Jul 24, 2021 » Contribute » Show contributors
Contributors: Alberto Ferrari, Marco Russo
Microsoft documentation: https://docs.microsoft.com/en-us/dax/blank-function-dax