VALUES and DISTINCT in Power BI - Step-by-Step Guide

Introduction

This feature helps you get a list of unique values from a column in your data. It solves the problem of duplicates when you want to see or use only distinct items in your reports or calculations.

When you want to create a slicer that shows only unique product names without repeats.

When you need to count how many different customers bought something.

When you want to filter a table to show only one row per category.

When you want to create a measure that works with unique dates in your sales data.

When you want to remove duplicate entries from a list before using it in calculations.

Steps

Step 1: Open

- Power BI Desktop

The main report view with your data model is visible

Step 2: Click

- Modeling tab

Modeling options appear in the ribbon

Step 3: Click

- New measure

A formula bar opens to write a DAX expression

Step 4: Type

- formula bar

You enter a DAX formula using VALUES or DISTINCT to get unique values from a column

💡 For example, type: UniqueProducts = DISTINCT('Sales'[ProductName])

Step 5: Press

- Enter key

The measure is created and added to the Fields pane

Step 6: Add

- a table visual on the report canvas

The table shows the unique values from the column you selected

Before vs After

Before

A table visual shows 100 rows with repeated product names like 'Apple' appearing 10 times

After

The table visual shows 15 rows with each product name listed only once, no repeats

Settings Reference

VALUES function

📍 DAX formula bar

Returns a one-column table of unique values from the specified column, including blanks if present

Default: No default, you must specify a column

DISTINCT function

📍 DAX formula bar

Returns a one-column table of unique values from the specified column, including blanks if present

Default: No default, you must specify a column

Common Mistakes

Using VALUES when you want to exclude blanks but blanks remain

VALUES includes blank values if they exist in the column

Use DISTINCT if you want unique values excluding blanks or add a filter to remove blanks

Trying to use VALUES or DISTINCT on a table instead of a column

Both functions require a single column as input, not a whole table

Specify the column inside the function, like VALUES('Table'[Column])

Summary

VALUES and DISTINCT help you get unique values from a column in your data.

VALUES includes blanks, DISTINCT returns unique values including blanks.

Use these functions in measures or calculated tables to clean or summarize data.

Practice

1. What is the main difference between the DAX functions VALUES and DISTINCT?

easy

A. VALUES returns unique values including blanks, DISTINCT returns unique values excluding blanks.

B. VALUES returns unique values and blanks, DISTINCT returns unique values including blanks.

C. VALUES returns unique values excluding blanks, DISTINCT excludes blanks.

D. VALUES and DISTINCT are exactly the same in all cases.

Solution

1. Step 1: Understand VALUES behavior

   VALUES returns unique values from a column and includes blank values if they exist.

2. Step 2: Understand DISTINCT behavior

   DISTINCT returns unique values but excludes blank values from the result.

3. Final Answer:

   VALUES includes blanks, DISTINCT excludes blanks -> Option A

4. Quick Check:

   VALUES includes blanks, DISTINCT excludes blanks [OK]

Hint: Remember: VALUES keeps blanks, DISTINCT drops them [OK]

Common Mistakes:

• Thinking VALUES and DISTINCT always return the same results
• Assuming DISTINCT includes blanks
• Confusing the behavior of blank values in both functions

2. Which of the following is the correct syntax to get unique values from the column Product[Category] using DISTINCT?

easy

A. DISTINCT(Product[Category])

B. DISTINCT(Product.Category)

C. VALUES(Product[Category])

D. VALUES(Product.Category)

Solution

1. Step 1: Check correct column reference syntax

   In DAX, columns are referenced with table name and column name inside square brackets, like Product[Category].

2. Step 2: Check function syntax

   Both VALUES and DISTINCT take a column reference in parentheses. The correct syntax is DISTINCT(Product[Category]).

3. Final Answer:

   DISTINCT(Product[Category]) -> Option A

4. Quick Check:

   Correct syntax uses square brackets and function call [OK]

Hint: Use square brackets for columns inside functions [OK]

Common Mistakes:

• Using dot notation instead of square brackets
• Missing parentheses after function name
• Using incorrect column references

3. Given a table Sales with a column CustomerID containing values [1, 2, 2, 3, BLANK, 3], what will be the result of COUNTROWS(VALUES(Sales[CustomerID]))?

medium

A. 6

B. 3

C. 4

D. 5

Solution

1. Step 1: Identify unique values including blanks

   The unique values in CustomerID are 1, 2, 3, and BLANK. That is 4 unique values.

2. Step 2: Apply COUNTROWS on VALUES

   VALUES returns unique values including blanks, so COUNTROWS counts 4 rows.

3. Final Answer:

   4 -> Option C

4. Quick Check:

   Unique values including blank = 4 [OK]

Hint: VALUES includes blanks, so count them too [OK]

Common Mistakes:

• Ignoring blank values in count
• Counting duplicates multiple times
• Confusing DISTINCT behavior here

4. You wrote this DAX measure: UniqueProducts = DISTINCT(Product[ProductName]). When you use it in a card visual, it shows an error. What is the problem?

medium

A. The column name is incorrect; it should be ProductName[Product].

B. DISTINCT returns a table, but card visuals need a single value.

C. DISTINCT cannot be used in measures, only in calculated columns.

D. You need to wrap DISTINCT with SUM to get a number.

Solution

1. Step 1: Understand what DISTINCT returns

   DISTINCT returns a table of unique values, not a single number or scalar value.

2. Step 2: Understand card visual requirements

   Card visuals require a single scalar value, like a number or text, not a table.

3. Final Answer:

   DISTINCT returns a table, but card visuals need a single value. -> Option B

4. Quick Check:

   DISTINCT returns table, card needs scalar [OK]

Hint: DISTINCT returns tables; use aggregation for single values [OK]

Common Mistakes:

• Using DISTINCT directly in measures for visuals needing scalars
• Incorrect column references
• Thinking DISTINCT returns a number

5. You want to create a slicer that shows only unique non-blank customer names from the Customers[Name] column. Which DAX expression should you use to create a calculated table for this slicer?

hard

A. CustomerNames = FILTER(DISTINCT(Customers[Name]), NOT(ISBLANK(Customers[Name])))

B. CustomerNames = VALUES(Customers[Name])

C. CustomerNames = FILTER(VALUES(Customers[Name]), NOT(ISBLANK(Customers[Name])))

D. CustomerNames = DISTINCT(Customers[Name])

Solution

1. Step 1: Understand the need to exclude blanks

   Both VALUES and DISTINCT return unique values, but VALUES includes blanks while DISTINCT excludes them.

2. Step 2: Choose function and filter blanks

   DISTINCT returns unique values excluding blanks, which is perfect for a slicer.

3. Step 3: Compare options

   CustomerNames = DISTINCT(Customers[Name]) directly provides unique non-blank names without needing extra filtering.

4. Final Answer:

   CustomerNames = DISTINCT(Customers[Name]) -> Option D

5. Quick Check:

   DISTINCT excludes blanks for clean slicer [OK]

Hint: DISTINCT excludes blanks automatically [OK]

Common Mistakes:

• Using VALUES without filtering blanks
• Assuming DISTINCT includes blanks
• Using incorrect column references in FILTER conditions