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Microsoft

PL-300 · Question #408

You have a Power BI semantic model that contains two queries. You discover that a report based on the model has performance issues. You plan to use Power Query to reduce the data loaded to the…

The correct answer is A. Apply group by and summarize techniques. C. Remove unnecessary columns and rows. To reduce the data loaded to a Power BI model and improve performance using Power Query, you should apply group by and summarize techniques, and remove unnecessary columns and rows.

Submitted by priya_blr· Apr 18, 2026

Question

You have a Power BI semantic model that contains two queries. You discover that a report based on the model has performance issues. You plan to use Power Query to reduce the data loaded to the model. Which two actions should you perform? Each correct answer presents part of the solution. NOTE: Each correct answer is worth one point.

Options

  • AApply group by and summarize techniques.
  • BCombine the queries by using Append.
  • CRemove unnecessary columns and rows.
  • DCombine the queries by using Merge.
  • ECreate a new query group.

How the community answered

(39 responses)
  • A
    72% (28)
  • B
    15% (6)
  • D
    5% (2)
  • E
    8% (3)

Why each option

To reduce the data loaded to a Power BI model and improve performance using Power Query, you should apply group by and summarize techniques, and remove unnecessary columns and rows.

AApply group by and summarize techniques.Correct

Applying 'group by' and summarize techniques reduces the number of rows loaded into the model by aggregating detailed data, which significantly improves query performance and refresh times.

BCombine the queries by using Append.

Combining queries using Append adds rows, which can increase the data loaded if not coupled with other data reduction steps, thereby potentially worsening performance.

CRemove unnecessary columns and rows.Correct

Removing unnecessary columns and rows directly decreases the volume and complexity of data imported into the model, leading to faster processing and better overall report performance.

DCombine the queries by using Merge.

Combining queries using Merge joins columns, which can also increase data volume and complexity, especially if not used to filter or summarize data effectively.

ECreate a new query group.

Creating a new query group is an organizational action within Power Query Editor and does not affect the amount of data loaded or the model's performance.

Concept tested: Power Query data reduction techniques

Source: https://learn.microsoft.com/en-us/power-bi/guidance/power-query-folding

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