Does an alternate key prevent duplicate rows in a Dataverse table?

PL-200 By islever Editorial Last updated

Short answer

A Creating an alternate key on the selected columns enforces a uniqueness constraint in Dataverse, so duplicate rows cannot be created.

Question

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 an alternate key for the columns. Does the solution meet the goal?
  1. Yes Correct Answer
  2. No

Key Takeaways

This item tests whether you know that a Dataverse alternate key is a real uniqueness constraint on the table — not merely an indexing or integration shortcut — while the trap is assuming duplicates are only blocked in specific app surfaces.

The scenario asks whether creating an alternate key on a Dataverse table's columns satisfies a requirement that the table contain no duplicate rows. Because alternate keys enforce a uniqueness constraint on the combined column values, the solution does meet the goal.

Common mistake: The most common wrong answer is "No," on the assumption that you must write a plug-in, Power Automate flow, or duplicate-detection rule to stop duplicates; those add conditional or UX-level checks, whereas an alternate key enforces uniqueness natively at the Dataverse platform level.

Expert Analysis

Why the Answer Is Correct

An alternate key in Dataverse is defined over one or more columns and acts as a permanent uniqueness constraint for the table. When a key is created on Name, Company, and Contacted On, Dataverse rejects any insert or update that would produce a second row with the same combination of values, regardless of whether the record arrives from a canvas app, a model-driven app, an import, or the Web API. That is exactly the stated requirement: "the table not contain any duplicate rows when users create data in the environment." Because both canvas and model-driven apps write through the same Dataverse platform, the constraint applies everywhere without extra code. Therefore the solution meets the goal and Yes is correct.

Why the Other Options Are Wrong

"No" would only be defensible if alternate keys merely optimized lookups, or if uniqueness could be bypassed in canvas apps — neither is true; the key is enforced by the platform for every writer. A Power Automate flow or a pre-operation plug-in could also block duplicates, but they are heavier, asynchronous or error-prone, and they are not what the question proposes. Duplicate detection rules in Dataverse are a separate, user-configurable feature that surfaces warnings and can be ignored or disabled, so they are weaker than a hard alternate key constraint. Designers who answer "No" are usually thinking of those softer mechanisms.

Community Comment Notes

JohnChung states plainly that "an alternate key can ensure there is no duplicated record in a single table," which matches the platform behavior. DaanEp walks through the same reasoning: the key spans Name, Company, and Contacted On, so "users won't be able to insert rows with the same combination of values in these columns." MrEz raises the sharpest caveat — with data like "same name same date same company, e.g. 2 phone calls" a business may legitimately need both rows, meaning the key is technically correct for the requirement but could over-constrain real data. That is a design consideration, not a reason the solution fails this question.

Exam Strategy

For PL-200 "Does the solution meet the goal?" items, judge only the mechanism named in the proposed solution against the stated requirement — here, does an alternate key block duplicate rows? Yes. Do not over-think business-edge semantics (such as date/time granularity) unless the question explicitly makes them part of the goal.

Frequently Asked Questions

Why does an alternate key stop duplicate rows in Dataverse?

An alternate key is a platform-level uniqueness constraint over one or more columns, so Dataverse rejects any insert or update that repeats the same combined values, no matter which app writes the row.

Would a Power Automate flow or duplicate detection rule be better here?

No. Flows and duplicate detection rules are conditional or advisory and can be bypassed or disabled, while an alternate key is a hard constraint enforced by Dataverse itself.

More PL-200 FAQ →

Community Votes

A
100%

100% of anonymous learners picked answer A. Votes are pick records left by other test-takers — they are not the verified answer.

Discussion 3 contributions

Compiled from public community threads and reader submissions, lightly edited for clarity. Handles and vote tallies are shown as recorded, and comments reflect the views of individual contributors.

From public community threads 3

  1. MrEz 👍 1
    you can make alternate keys with multiple fields name and company and contacted on. but there are 3 problems: we don't know if contacted on is date and time or date only. same name same date same company, e.g. 2 phone calls --> needs to be saved because one was in the morning and one was in the afternoon. :-) Name = standard field? like subject? if by chance the have the same topic and the user enters the same name. e.g. 2 different people call from the same company at the same time and the customer helpdesk agents enter 'super bowl ticket expiration' for name ... you are doomed. okay maybe name is fullname George W. Bush, working both (senior and junior) for Carlyle group and both have a scheduled call at 08:15 for the same company... but technically you can. yes we can.
  2. DaanEp 👍 1 Answered A
    you want to ensure that there are no duplicate rows based on the "Name," "Company," and "Contacted On" columns. Creating an alternate key for these columns will enforce this uniqueness constraint, and users won't be able to insert rows with the same combination of values in these columns. So, the solution of creating an alternate key aligns with the goal of preventing duplicate rows, and it is a valid approach in Dataverse.
  3. JohnChung 👍 1 Answered A
    An alternate key can ensure there is no duplicated record in a single table

Reader comments & corrections

No reader corrections yet — spotted an error or have a note? Share it below.

Log in to comment, report an error, or add a note about this question.

How Do You Lock a Power Pages Chatbot to Entra ID Users?

S-grade

Preventing Table Display Name Changes in UAT

S-grade

Minimizing Dataverse Storage with SharePoint Integration

S-grade

Power Apps Environment Variable Resolution in Managed Solutions

S-grade

← Back to PL-200 Study Guide