DirectQuery vs Import mode in Power BI - Practice Questions

Challenge - 5 Problems

🧠 Conceptual

intermediate

Difference in Data Refresh Frequency

Which statement correctly describes the data refresh behavior when using DirectQuery mode compared to Import mode in Power BI?

A Both DirectQuery and Import mode query the data source live on each interaction.

B DirectQuery mode queries the data source live on each interaction, while Import mode requires scheduled or manual refresh to update data.

C Both DirectQuery and Import mode require manual refresh to update data.

D Import mode queries the data source live on each interaction, while DirectQuery requires scheduled or manual refresh to update data.

💡 Hint

Think about how data is accessed in real-time versus stored locally.

DirectQuery mode sends queries directly to the data source every time you interact with the report, so data is always current. Import mode loads data into Power BI's memory and needs refreshes to update.

🎯 Scenario

intermediate

Choosing Mode for Large Dataset

You have a very large dataset that cannot fit into Power BI's memory. You want to build reports that always show the latest data without waiting for scheduled refreshes. Which mode should you choose?

A DirectQuery mode, because it queries the data source live and handles large datasets without loading all data into memory.

B Import mode, because it loads data into memory for faster queries.

C Neither mode can handle large datasets efficiently.

D Use Import mode with incremental refresh to handle large datasets.

💡 Hint

Consider how each mode handles data size and freshness.

DirectQuery mode is designed to work with large datasets by querying the source live, avoiding memory limits. Import mode loads data into memory, which can be problematic for very large datasets.

❓ dax_lod_result

advanced

DAX Query Behavior in DirectQuery Mode

Consider a Power BI report using DirectQuery mode connected to a SQL database. You create this DAX measure:

Sales Amount = SUM(Sales[Amount])

What happens when you interact with a slicer filtering by Product Category?

A Power BI caches all data on first load and does not query the database again.

B Power BI loads all Sales data into memory and applies the filter locally.

C Power BI ignores the slicer filter and returns total sales for all categories.

D Power BI sends a SQL query to the database with a WHERE clause filtering by the selected Product Category, returning only relevant data.

💡 Hint

Think about how DirectQuery mode handles filtering and queries.

In DirectQuery mode, Power BI translates DAX filters into SQL queries with WHERE clauses, so only filtered data is retrieved from the source.

🔧 Formula Fix

advanced

Performance Issue in DirectQuery Mode

A report using DirectQuery mode is very slow when filtering on a date column. Which of the following is the most likely cause?

A The report uses Import mode, which is slower than DirectQuery.

B Power BI caches too much data locally, causing memory overflow.

C The date column is not indexed in the source database, causing slow query performance.

D The data model has too many calculated columns in Power BI.

💡 Hint

Think about what affects query speed in the source database.

In DirectQuery mode, queries run on the source database. If columns used for filtering are not indexed, queries can be slow.

❓ visualization

expert

Visualizing Data Freshness Differences

You want to create a dashboard that clearly shows users the difference in data freshness between Import mode and DirectQuery mode. Which visualization approach best communicates this difference?

A Use a gauge visual showing last refresh time for Import mode and a live clock for DirectQuery mode.

B Use a pie chart showing percentage of data loaded in memory.

C Use a bar chart comparing total sales for both modes without timestamps.

D Use a table listing all data rows from both modes side by side.

💡 Hint

Think about how to show data freshness clearly and simply.

A gauge showing last refresh time for Import mode and a live clock for DirectQuery mode visually communicates how current the data is in each mode.