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This article introduces logical functions and their uses in Tableau. It also demonstrates how to create a logical calculation using an example.

Why use logical calculations

Logical calculations allow you to determine if a certain condition is true or false (boolean logic). For example, you might want to quickly see if sales for each country you distribute your merchandise to were above or below a certain threshold.

The logical calculation might look something like this:

SUM(Sales) > 1,000,000

Logical functions available in Tableau:

Function

Syntax

Description

IN IN

Returns TRUE if any value in matches any value in .

The values in can be a set, list of literal values, or combined field.

Examples:

SUM([Cost]) IN (1000, 15, 200)

[Field] IN [SET]

AND

IF AND THEN END

Performs a logical conjunction on two expressions.

Example:

IF (ATTR([Market]) = "New Business" AND SUM([Sales]) > [Emerging Threshold] )THEN "Well Performing"

CASECASE WHEN THEN WHEN THEN ... ELSE END

Performs logical tests and returns appropriate values. The CASE function evaluates IN 0, compares it to a sequence of values, IN 1, IN 2, etc., and returns a result. When a value that matches IN 0 is encountered, CASE returns the corresponding return value. If no match is found, the default return expression is used. If there is no default return and no values match, then Null is returned.

CASE also supports WHEN IN construction, such as

IN 4

The values that WHEN IN compare to must be a set, list of literal values, or combined field.

Additional notes

• CASE versus IF: CASE is often easier to use than IIF or IF THEN ELSE. Typically, an IF function performs a sequence of arbitrary tests, and a CASE function searches for a match to an expression. But a CASE function can always be rewritten as an IF function, although the CASE function will generally be more concise.
• CASE versus groups: Many times you can use a group to get the same results as a complicated CASE function. You may want to see which is more performant for your scenario.

Examples:

IN 5

IN 6

ELSE IN 7

Tests a series of expressions returning the value for the first true .

Example:

IN 8

ELSEIF IN 9

Tests a series of expressions returning the value for the first true .

Example:

0

END IN 9

Tests a series of expressions returning the value for the first true . Must be placed at the end of an expression.

Example:

0

IF IN 9

Tests a series of expressions returning the value for the first true .

Example:

0

IFNULL5

Returns if it is not null, otherwise returns .

Example:

6

IIF7

Checks whether a condition is met, and returns one value if TRUE, another value if FALSE, and an optional third value or NULL if unknown.

Example:

8

ISDATE9

Returns true if a given string is a valid date.

Example:

0

ISNULL1

Returns true if the expression is NULL (does not contain valid data).

Example:

2

MAX3 or 4

Returns the maximum of a single expression across all records or the maximum of two expressions for each record.

Example:

5

MIN6 or 7

Returns the minimum of an expression across all records or the minimum of two expressions for each record.

Example:

8

NOT9

Performs logical negation on an expression.

Example:

0

OR1

Performs a logical disjunction on two expressions.

Example:

2

THEN3

Tests a series of expressions returning the value for the first true .

Example:

4

WHEN5

Finds the first that matches and returns the corresponding .

Example:

6

ZN7

Returns if it is not null, otherwise returns zero.

Example:

8

Note: some of these are actually logical operators and appear in black, not blue. For more information, see .

Create a logical calculation

Follow along with the steps below to learn how to create a logical calculation.

1. In Tableau Desktop, connect to the Sample - Superstore saved data source, which comes with Tableau.

2. Navigate to a worksheet.

3. From the Data pane, drag State to the Rows shelf.

4. From the Data pane, drag Category to the Rows shelf and place it to the right of State.

5. From the Data pane, drag Sales to the Columns shelf.

6. Select Analysis > Create Calculated Field.

7. In the calculation editor that opens, do the following:

• Name the calculated field, KPI.

• Enter the following formula:

  9

  This calculation quickly checks if a member is great than zero. If so, it returns true; if not, it returns false.

• When finished, click OK.

  The new calculated field appears under Measures in the Data pane. Just like your other fields, you can use it in onr or more visualizations.