DP-700 Monitor and Optimize an Analytics Solution Practice Question
You are monitoring a Dataflow Gen2 refresh in Microsoft Fabric. The refresh fails with an error: 'Mashup Evaluation Error'. What is the most common cause of this error when working with large datasets in Dataflows?
⚠ Common exam trap
Examinees often guess that network connectivity issues or gateway failures caused the Mashup Evaluation Error, ignoring resource limitations inside the cloud-based Power Query engine.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The transformation logic is too memory-intensive for the evaluator.
Dataflow Gen2 uses the Power Query engine for data transformation. A 'Mashup Evaluation Error' often occurs when the engine runs out of memory or hits a timeout while processing complex transformations or large volumes of data. Understanding the limitations of the Power Query online evaluator is key to designing robust data ingestion processes.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The destination Lakehouse has reached its storage limit.
Why it's wrong here
If a storage limit were hit, the error would typically be specific to the 'write' phase and mention disk space or quota issues. A mashup evaluation error occurs during the 'transform' phase within the Power Query engine, before the data is successfully committed to the final destination.
- ✓
The transformation logic is too memory-intensive for the evaluator.
Why this is correct
Complex steps like 'Group By' on high-cardinality columns, multiple joins, or large 'Sort' operations can exceed the memory allocated to the Power Query mashup container. Simplifying the steps or using 'staged queries' to break up the logic can often resolve these types of evaluation errors.
- ✗
The Spark pool assigned to the Dataflow is offline.
Why it's wrong here
Dataflow Gen2 does not use a Spark pool that you manage; it uses its own internal compute resources and the 'High Performance' compute (which is backed by Fabric SQL) for staging. Therefore, an 'offline Spark pool' is not a valid reason for a mashup error in this context.
- ✗
The user does not have 'Execute' permissions on the Dataflow.
Why it's wrong here
If a user lacked permissions, they would be unable to start the refresh at all, and an 'Unauthorized' error would be shown. Since the refresh actually started and then failed with a 'Mashup' error, the issue is clearly related to the execution logic or data rather than security.
About these practice questions
This DP-700 question is part of Courseiva's 152-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Microsoft exam blueprint
This DP-700 practice question is part of Courseiva's free Microsoft certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the DP-700 exam.