How do you read data from the Dataverse Web API?

Required tools

• An application user in Entra ID — Do not use a personal account for the integration.
• Access to the environment URL — The format is organisasjon.crm4.dynamics.com.

Set up access

1. 1.Register an application in Entra ID

   The integration should have its own identity rather than borrowing someone else's. That way, it will continue to work when someone changes jobs, and its permissions can be limited to only what it actually needs.

2. 2.Create a corresponding application user in Dataverse

   The application must exist as a user in the environment and be assigned a security role. This step is often overlooked, and the symptom is that authentication succeeds while all queries return empty results.

3. 3.Get an access token

   The application authenticates with Entra ID and receives a token that is included with every call. The token has a limited lifetime and must be renewed—build this in from the start.

Request data

1. 4.Start with a simple query

   Fetch a few rows from a single table and confirm that you get a response. That way, you know that access and authentication are working before you build anything more.

2. 5.Only request the fields you need

   Without limiting the selection, all columns are returned. This is slow and unnecessary, and the impact is immediately noticeable on large tables.

3. 6.Manage pagination

   Large result sets are returned in pages with a link to the next page. An integration that does not follow that link will silently retrieve only the first page—an error that can go unnoticed for a long time.

4. 7.Respect the call limits

   There are limits per unit of time. Build in pauses and retries when requests are rejected, rather than letting the integration stop completely.