SELECTEDVALUE and HASONEVALUE in Power BI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to return the selected product name or "Unknown" if none is selected.

Power BI

ProductName = SELECTEDVALUE('Products'[Name], [1])

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

ABLANK()

B"Unknown"

C"None"

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Leaving the alternate value blank causes errors when multiple or no values are selected.

Using 0 instead of a string for alternate value.

The SELECTEDVALUE function returns the selected value if there is only one, otherwise it returns the alternate result. Here, "Unknown" is used as the alternate.

2fill in blank

medium

Complete the code to check if exactly one year is selected in the 'Date' table.

Power BI

IsSingleYearSelected = HASONEVALUE([1])

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

A'Date'[Year]

B'Sales'[Year]

C'Date'[Month]

D'Products'[Year]

Attempts:

3 left

💡 Hint

Common Mistakes

Using a column from the wrong table.

Forgetting to use single quotes around the table name.

HASONEVALUE checks if exactly one distinct value is selected in the specified column. Here, we want to check the Year column in the Date table.

3fill in blank

hard

Fix the error in the measure that returns the selected category or "Multiple" if more than one is selected.

Power BI

SelectedCategory = IF(HASONEVALUE('Categories'[Category]), [1], "Multiple")

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

AFIRSTNONBLANK('Categories'[Category], 1)

BVALUES('Categories'[Category])

CSELECTEDVALUE('Categories'[Category])

DDISTINCT('Categories'[Category])

Attempts:

3 left

💡 Hint

Common Mistakes

Using VALUES which returns a table, causing errors.

Using DISTINCT which also returns a table.

The SELECTEDVALUE function returns the single selected value or blank if multiple are selected. Inside the IF, it is the correct function to use to get the selected category.

4fill in blank

hard

Fill both blanks to create a measure that returns the selected region or "All Regions" if none or multiple are selected.

Power BI

SelectedRegion = IF(HASONEVALUE([1]), SELECTEDVALUE([2]), "All Regions")

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

A'Regions'[Region]

B'Sales'[Region]

D'Products'[Region]

Attempts:

3 left

💡 Hint

Common Mistakes

Using different tables for HASONEVALUE and SELECTEDVALUE.

Using columns from unrelated tables.

Both blanks require the same column reference from the Regions table's Region column to check and return the selected region.

5fill in blank

hard

Fill all three blanks to create a measure that returns the selected product or "Multiple Products" if more than one is selected, or "No Product" if none is selected.

Power BI

ProductStatus = IF(HASONEVALUE([1]), SELECTEDVALUE([2]), IF(ISBLANK(SELECTEDVALUE([3])), "No Product", "Multiple Products"))

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

A'Products'[ProductName]

D'Sales'[ProductName]

Attempts:

3 left

💡 Hint

Common Mistakes

Using different tables for the blanks.

Not handling the no selection case properly.

All blanks refer to the same column 'Products'[ProductName] to check selection and return appropriate messages.

Practice

1. What does the SELECTEDVALUE function do in Power BI?

easy

A. Filters the data to only one selected value

B. Checks if exactly one value is selected

C. Returns all selected values as a list

D. Returns the single selected value or a default if multiple values are selected

Solution

1. Step 1: Understand the purpose of SELECTEDVALUE

   SELECTEDVALUE returns a single value if only one is selected; otherwise, it returns a default or blank.

2. Step 2: Compare with other options

   HASONEVALUE checks selection count, not returning the value itself; other options describe different behaviors.

3. Final Answer:

   Returns the single selected value or a default if multiple values are selected -> Option D

4. Quick Check:

   SELECTEDVALUE = single value or default [OK]

Hint: SELECTEDVALUE gives one value or default if many selected [OK]

Common Mistakes:

• Confusing SELECTEDVALUE with HASONEVALUE
• Thinking SELECTEDVALUE returns all selected values
• Assuming SELECTEDVALUE filters data

2. Which of the following is the correct syntax for using HASONEVALUE in a DAX measure?

easy

A. HASONEVALUE = ColumnName

B. HASONEVALUE[ColumnName]

C. HASONEVALUE(ColumnName)

D. HASONEVALUE(ColumnName, DefaultValue)

Solution

1. Step 1: Recall HASONEVALUE syntax

   HASONEVALUE takes a single column as argument to check if exactly one value is selected.

2. Step 2: Eliminate incorrect syntax

   Options A, C, and D do not follow correct function call syntax or add invalid parameters.

3. Final Answer:

   HASONEVALUE(ColumnName) -> Option C

4. Quick Check:

   HASONEVALUE(Column) syntax correct [OK]

Hint: HASONEVALUE takes one column as argument in parentheses [OK]

Common Mistakes:

• Using equal sign instead of parentheses
• Adding extra parameters to HASONEVALUE
• Using square brackets incorrectly

3. Given the following DAX measure:

Selected Product = SELECTEDVALUE('Products'[ProductName], "Multiple")

If the user selects exactly one product named "Chair", what will the measure return?

medium

A. "Chair"

B. "Multiple"

C. Blank

D. Error

Solution

1. Step 1: Understand SELECTEDVALUE behavior with one selection

   When exactly one value is selected, SELECTEDVALUE returns that value, here "Chair".

2. Step 2: Consider the default value

   The default "Multiple" is returned only if multiple or no values are selected, which is not the case here.

3. Final Answer:

   "Chair" -> Option A

4. Quick Check:

   One value selected = returns that value [OK]

Hint: One selected value returns it, else default [OK]

Common Mistakes:

• Assuming default value returns even with one selection
• Confusing blank with default
• Expecting error on multiple selections

4. You wrote this DAX measure:

IsSingleCategory = IF(HASONEVALUE('Sales'[Category]), SELECTEDVALUE('Sales'[Category]), "Multiple")

But it always returns "Multiple" even when one category is selected. What is the likely problem?

medium

A. The HASONEVALUE function is used incorrectly without a filter context

B. SELECTEDVALUE cannot be used inside IF statements

C. The column name 'Category' is misspelled

D. The measure lacks a default value in SELECTEDVALUE

Solution

1. Step 1: Analyze HASONEVALUE usage

   HASONEVALUE depends on filter context; if no filter is applied, it returns FALSE even if one value exists.

2. Step 2: Understand why measure returns "Multiple"

   Without proper filter context, HASONEVALUE returns FALSE, so IF returns "Multiple" always.

3. Final Answer:

   The HASONEVALUE function is used incorrectly without a filter context -> Option A

4. Quick Check:

   HASONEVALUE needs filter context to work [OK]

Hint: HASONEVALUE needs filter context to return TRUE [OK]

Common Mistakes:

• Assuming SELECTEDVALUE can't be inside IF
• Ignoring filter context importance
• Not checking column spelling

5. You want to create a measure that shows the selected product name if exactly one product is selected, otherwise shows "Multiple Products". Which DAX expression correctly achieves this?

hard

A. Product Selected = IF(SELECTEDVALUE('Products'[ProductName]), HASONEVALUE('Products'[ProductName]), "Multiple Products")

B. Product Selected = IF(HASONEVALUE('Products'[ProductName]), SELECTEDVALUE('Products'[ProductName]), "Multiple Products")

C. Product Selected = SELECTEDVALUE('Products'[ProductName], HASONEVALUE('Products'[ProductName]))

D. Product Selected = HASONEVALUE('Products'[ProductName]) & SELECTEDVALUE('Products'[ProductName])

Solution

1. Step 1: Understand the requirement

   Show product name if exactly one selected; else show "Multiple Products".

2. Step 2: Evaluate each option

   Product Selected = IF(HASONEVALUE('Products'[ProductName]), SELECTEDVALUE('Products'[ProductName]), "Multiple Products") uses HASONEVALUE to check selection count and SELECTEDVALUE to get the name, with fallback text. Others misuse functions or syntax.

3. Final Answer:

   Product Selected = IF(HASONEVALUE('Products'[ProductName]), SELECTEDVALUE('Products'[ProductName]), "Multiple Products") -> Option B

4. Quick Check:

   HASONEVALUE + SELECTEDVALUE with IF = correct pattern [OK]

Hint: Use IF with HASONEVALUE and SELECTEDVALUE for conditional display [OK]

Common Mistakes:

• Passing HASONEVALUE as default to SELECTEDVALUE
• Using SELECTEDVALUE as condition in IF
• Concatenating HASONEVALUE and SELECTEDVALUE incorrectly