Can Power Fx Formula Columns Prevent Duplicate Dataverse Rows?
Note: This question is part of a series of questions that present the same scenario. Each question in the series contains a unique solution that might meet the stated goals. Some question sets might have more than one correct solution, while others might not have a correct solution. After you answer a question in this section, you will NOT be able to return to it. As a result, these questions will not appear in the review screen. A company uses a Dataverse environment. The environment is accessed from canvas and model-driven apps. The Dataverse environment contains a table that has the following columns: • Name • Company • Contacted On The company requires that the table not contain any duplicate rows when users create data in the environment. You need to implement a solution that meets the requirement. Solution: Create a Microsoft Power Fx formula for the columns. Does the solution meet the goal?
Community Votes
75% of anonymous learners picked answer B. Votes are pick records left by other test-takers — they are not the verified answer.
Community Insight
This question tests the boundary between Power Fx formula columns and Dataverse duplicate enforcement; the trap is assuming a UI-level formula can stop duplicates from every app and integration.
Creating a Power Fx formula for the columns does not prevent duplicate rows in a Dataverse table. This page establishes that the solution fails because formula columns calculate per-row values and cannot enforce table-wide uniqueness.
Choosing Yes because Power Fx can check existing data before save in a canvas app; however, that check is app-specific and does not stop duplicates from model-driven apps, imports, or APIs.
Community Discussion (3 comments)
Comments & Corrections
No comments yet — spotted an error or have a note? Share it below.
Expert Analysis
Why the Answer Is Correct
The goal is to prevent any duplicate rows in the Dataverse table, which requires a table-level uniqueness constraint across Name, Company, and Contacted On. A Power Fx formula column is a calculated column: it derives a value from other columns in the same row and has no ability to scan the table for an existing match before a new row is saved. Even if a canvas app uses Power Fx to compare values, that check runs only in that app and does not stop duplicates created by model-driven apps, imports, APIs, or plugins. Because the solution cannot enforce table-wide duplicate prevention, B (No) is the correct answer.Why the Other Options Are Wrong
Option A (Yes) assumes a Power Fx formula can validate existing data before save, as nqthien041292 suggested, but that would be app-level logic at best and would not create a database constraint. Formula columns cannot act as alternate keys or duplicate detection rules; they simply calculate and display values per row. Masbee's comment correctly states that Power Fx formulas are mainly for "calculations, validations, or conditional logic at the UI level", not for enforcing uniqueness constraints at the database level. Therefore the solution does not meet the stated requirement.Community Comment Notes
Masbee's answer (B) explains that Power Fx formulas are "primarily used for calculations, validations, or conditional logic" in Power Apps rather than in the Dataverse database. nqthien041292 voted Yes and proposed using Power Fx to check existing data before save, but that approach is bypassed by other clients and bulk data operations. businesselements1 shared the Microsoft Power Fx overview link, which defines formula columns as calculated columns and supports the conclusion that they are not an integrity mechanism.Official Reference
Exam Strategy
For Dataverse uniqueness questions, look for alternate keys or duplicate detection rules rather than Power Fx formulas. Remember that formula columns are calculated per row and cannot scan the table for existing duplicates.
Frequently Asked Questions
Why doesn't a Power Fx formula column prevent duplicate Dataverse rows?
Formula columns compute a value for the current row using Power Fx; they cannot query the table to block an insert with the same Name, Company, and Contacted On values.
What Dataverse feature should be used instead to stop duplicate rows?
Define an alternate key or a duplicate detection rule on the table, which Dataverse enforces at the platform level for canvas and model-driven apps.