Tableau provides various Logical Functions to perform logical operations on our data. They are Tableau AND, NOT, OR, IF, ELSEIF, IF Else, CASE, ISNULL, IFNULL, ZN, IIF, etc. In this article, we will show you how to use Tableau Logical Functions with examples.
To demonstrate these Tableau Logical Functions, we are going to use the data present in the Global Super Store Excel Worksheet. So, Please refer to Connecting to Excel Files in Tableau article to understand the connection settings.

Tableau Logical Functions
The following examples will show you the list of Logical Functions in Tableau
Tableau AND Function
The Tableau AND function is used to check multiple expressions. The syntax of the Tableau AND Function is as shown below:
Expression_1 AND Expression_2
As you see from the above syntax, Tableau AND function accept two arguments. If both the conditions are True, it returns True. Otherwise, it returns False.
To demonstrate these logical functions in Tableau, we have to use Calculated Fields. To create a calculated field, please navigate to Analysis Tab and select the Create Calculated Field… option

Once you click on the Create Calculated Field… option, following window will be opened. Here, we renamed the default calculation name as AND Function.
It will check whether the Profit is greater than 0, and Quantity is greater than 25000. If both these conditions are true, the Tableau logical AND function will return Good; otherwise, it will return Bad
IF(SUM([Profit]) > 0 AND SUM(Quantity) > 25000) THEN 'Good' ELSE 'Bad' END

Let me add this AND function calculated field to the table (by dragging a field to Rows Shelf). Please refer Create Table Report article to understand the process of creating a table

Tableau OR Function
The Tableau OR function is like either or statement in English. If both the conditions are False, Tableau or will return False; otherwise, it returns True. The syntax of this Tableau OR Function is:
Expression_1 OR Expression_2
The below statement will return Good if either of these two statements is True
IF(SUM([Profit]) > 0 OR SUM(Quantity) > 300000) THEN 'Good' ELSE 'Bad' END

Let me add this field to the Rows shelf

Tableau IIF Function
The Tableau IIF function is the simple version of the If Else Function. If both the condition is True, then it will return First Statement otherwise, the second statement. The syntax of this Tableau IIF Function is:
IIF(Expression, True_statement, False_Statement)
The following Tableau IIF function returns Profit if the condition is True. Otherwise, Loss will return.
IIF(SUM([Profit]) > 0, 'Profit', 'Loss')

Now you can see the result of the Table IIF function

Tableau NOT Function
The Tableau NOT function return the exact opposite. I mean, True will become false and vice versa. The syntax of this Tableau NOT Function is:
NOT(Expression)
The below Tableau Not statement will return Loss if the condition is True. Otherwise, Profit will return.
IF(NOT SUM([Profit]) > 0) THEN 'Profit' ELSE 'Loss' END

You can see the NOT function result by yourself

Tableau ISNULL Function
To demonstrate this Tableau ISNULL function, we will use the below shown table.

Tableau ISNULL function will check whether it is NULL or Not. If it is NULL, then it returns TRUE; otherwise, False will return.
The syntax of the Tableau ISNULL Function is:
ISNULL(Expression)
The following statement will check nulls in Service Grade 2 column.
ISNULL([Service Grader 2])

As you can see, this Tableau ISNULL function returned True for the products under Blue Color.

Tableau ZN Function
Tableau ZN function will return the original values of Not Null values, and 0 for Null values. In simple English, ZN in Tableau is used to replace the NULL values with 0.
The syntax of the Tableau ZN Function is:
ZN(Expression)
The below Tableau logical function statement will replace NULL with 0.
ZN([Service Grader 2])

From the below screenshot, you can see the result of a Tableau ZN function.

Tableau IFNULL Function
Tableau IFNULL function is used to replace the NULL values with your own. The syntax of the Tableau IFNULL Function is:
IFNULL(Expression, Value)
The following Tableau ifnull statement will replace NULLs with 10.
IFNULL([Service Grader 2], 10)

Let us see the result of the Tableau IFNULL
