VALUES and DISTINCT in Power BI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to return a unique list of products from the Sales table.

Power BI

UniqueProducts = [1](Sales[Product])

Drag options to blanks, or click blank then click option'

AFILTER

BSUM

CVALUES

DCALCULATE

Attempts:

3 left

💡 Hint

Common Mistakes

Using SUM instead of VALUES returns a number, not unique values.

Using FILTER without a condition does not return unique values.

The VALUES function returns a one-column table of unique values from the specified column.

2fill in blank

medium

Complete the code to get a distinct list of customer IDs from the Customers table.

Power BI

DistinctCustomers = [1](Customers[CustomerID])

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ADISTINCT

BSUMMARIZE

CCOUNTROWS

DRELATED

Attempts:

3 left

💡 Hint

Common Mistakes

Using COUNTROWS returns a count, not unique values.

Using RELATED is for relationships, not for unique value lists.

The DISTINCT function returns a one-column table with unique values from the specified column.

3fill in blank

hard

Fix the error in the code to return unique product categories from the Products table.

Power BI

UniqueCategories = DISTINCT([1])

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AProducts->Category

BProducts[Category]

CProducts(Category)

DProducts.Category

Attempts:

3 left

💡 Hint

Common Mistakes

Using dot notation like Products.Category is invalid in DAX.

Using parentheses or arrows for column reference causes syntax errors.

In DAX, columns are referenced with square brackets inside the table name, like TableName[ColumnName].

4fill in blank

hard

Fill both blanks to create a measure that counts distinct customers who made sales.

Power BI

DistinctCustomerCount = COUNTROWS([1]([2]))

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AVALUES

BSales[CustomerID]

CDISTINCT

DCustomers[CustomerID]

Attempts:

3 left

💡 Hint

Common Mistakes

Using Customers[CustomerID] instead of Sales[CustomerID] counts all customers, not just those who made sales.

Using DISTINCT instead of VALUES works but here VALUES is preferred for this context.

First, use VALUES to get unique CustomerIDs from the Sales table, then count rows to get the number of distinct customers.

5fill in blank

hard

Fill all three blanks to create a table of distinct product names and their categories from the Products table.

Power BI

DistinctProducts = SUMMARIZE([1], [2], [3])

Drag options to blanks, or click blank then click option'

AProducts

BProducts[ProductName]

CProducts[Category]

DSales

Attempts:

3 left

💡 Hint

Common Mistakes

Using Sales table instead of Products returns unrelated data.

Using columns from different tables causes errors.

SUMMARIZE creates a summary table grouping by specified columns. Here, we group the Products table by ProductName and Category to get distinct combinations.

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