COUNT and DISTINCTCOUNT in Power BI - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the COUNT function do in Power BI?

The COUNT function counts the number of non-empty values in a column.

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What is the difference between COUNT and DISTINCTCOUNT?

COUNT counts all non-empty values, including duplicates.<br>DISTINCTCOUNT counts only unique non-empty values.

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Write a simple DAX formula to count all sales transactions in a table named Sales using COUNT.

Total Sales = COUNT(Sales[TransactionID])<br>This counts all non-empty TransactionID values.

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How would you count the number of unique customers in the Sales table?

Use DISTINCTCOUNT on the CustomerID column:<br>Unique Customers = DISTINCTCOUNT(Sales[CustomerID])

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Why is it important to use DISTINCTCOUNT when counting unique items?

Because it avoids counting duplicates, giving the true number of unique items, like unique customers or products.

What does COUNT(Sales[OrderID]) return?

A Number of empty OrderID values

B Number of unique OrderID values

C Total sum of OrderID values

D Number of non-empty OrderID values

COUNT counts all non-empty values, including duplicates.

Which function counts only unique values in a column?

A DISTINCTCOUNT

B SUM

C AVERAGE

D COUNT

DISTINCTCOUNT counts only unique non-empty values.

If a column has 10 values with 3 duplicates, what will DISTINCTCOUNT return?

A 7

B 3

C 10

D 13

DISTINCTCOUNT counts unique values, so duplicates are counted once.

Which DAX formula counts all rows where the column is not empty?

A COUNTROWS(Table)

B DISTINCTCOUNT(Table[Column])

C COUNT(Table[Column])

D SUM(Table[Column])

COUNT counts non-empty values in a column.

What will COUNT do with empty or blank values?

A Count them as zero

B Ignore them

C Count them as one

D Count only if they are text

COUNT ignores empty or blank values.

Explain in your own words the difference between COUNT and DISTINCTCOUNT in Power BI.

Think about counting all items versus counting only unique items.

Describe a real-life example where you would use DISTINCTCOUNT instead of COUNT.

Imagine you want to know how many different people bought something, not how many total purchases.