Power BI 778 Performance Optimization and Troubleshooting 3

Question 1

What is the dataset size limit per dataset in a Power BI Pro workspace when using Import mode?

Accepted Answer

1 GB

Answer

500 MB

Answer

10 GB

Answer

25 GB

Question 2

When writing DAX, which filtering approach is generally more performant for a simple equality condition on a single column?

Accepted Answer

CALCULATE([Measure], Table[Column] = Value)

Answer

FILTER(Table, Table[Column] = Value)

Answer

LOOKUPVALUE(Table[Column], Table[Key], Value)

Answer

IF(HASONEVALUE(Table[Column]), [Measure], BLANK())

Question 3

How does refactoring a denormalized flat table into a star schema reduce Power BI memory usage?

Accepted Answer

It replaces repeated text strings in the fact table with compact integer keys, improving compression

Answer

It removes all relationships, reducing model complexity

Answer

It forces all dimension tables into DirectQuery mode

Answer

It enables query folding on calculated columns

Question 4

In Power BI Premium, which feature enables Import mode for historical data partitions while using DirectQuery for the most recent real-time partition of the same table?

Accepted Answer

Incremental refresh with hybrid tables

Answer

Composite model

Answer

Dual storage mode

Answer

Live Connection with caching

Question 5

What DAX practice best reduces repeated evaluation of the same sub-expression within a complex measure?

Accepted Answer

Using VAR to store intermediate results and reference them multiple times

Answer

Nesting CALCULATE calls more deeply

Answer

Switching the dataset to DirectQuery mode

Answer

Adding more slicers to the report page

Question 6

What is the recommended way to set up time intelligence in Power BI for optimal DAX performance?

Accepted Answer

Create a dedicated date dimension table marked as a Date Table with a continuous date range

Answer

Calculate date differences with nested IF statements in measures

Answer

Add individual Year, Month, and Day columns to every fact table

Answer

Use DATEDIFF inside each time-based measure

Question 7

Which approach should you take first when a Power BI report page is slow to load, before making any model changes?

Accepted Answer

Use Performance Analyzer to identify which specific visual or DAX query is the bottleneck

Answer

Immediately switch all tables to DirectQuery mode

Answer

Delete all relationships and recreate them

Answer

Publish to Premium capacity and use larger node sizes