Dataflow refresh fails (but no errors in preview)

[JanKral]

Good day,

I am working on extension of one of my dataflows but I faced a problem I am not able to solve.

I have a dataflow which pulls data via an API (it's a REST API providing employees' data). Now, I want to create new dataflow which, for each active employee (column "state" is set to "active") I fetch additional infomration from another API endpoint.

I work in Pro workspace, so I am not able to reference my first dataflow, hence, some logic is repeated (i.e., pulling employees' data).

In new dataflow I created a function that calls API endpoint with employee number as a parameter and cleans data returning only fields I need. In a preview there are no errors. I am able to scroll through all rows (less than 200 active employees) and all data loads without any problems. However, when I save dataflow and set it to refresh I am getting an error. When I look at refresh logs I don't get much details 

Error:  Request ID: 7d0d4933-b6a6-73b6-ccc8-3286cbed9eb1 Activity ID: 830b261b-8ca0-46a2-843a-b7d4e933d4bb

I copied dataflow table into Power BI desktop to check if that causes any problems. But, the data loads without any problems whatsoever and data model loads in less than a minute.

How can I investigate the root cause of dataflow refresh failing?

[JanKral · Accepted solution]

The issue seems to be caused by the fuction returning details of each employee contract. It was returning a 1-row table which seem to be fine for power bi desktop and dataflow preview but dataflow refresh requires a record type to be returned (so that it can be expanded into additional columns).

Is it a bug or a feature? Do anyone know some source where I couls find more details about this behavior?

[tnemeth]

I made a topic VERY SIMILAR to this earlier this week. Clearly I didn't see your topic at the time.

Unfortunately (?) I have no idea what you meant and I started to google different things and one thing led to another and I ended up clicking 'Options' 'Privacy' and then 'Allow combining...' and that fixed my problem. I'll write a more detailed explanation in the topic I posted...

I DON'T think that what I discovered is entirely relevent to what you were saying your problem was but:

a) It could be -- I don't know enough to know it isn't

b) Reading your post set my google searches on the right track to get me to my answer - so thanks!