Missing data after refreshing dataflow.

[Anonymous]

Hello,

I have issues with my dataflows. In my dataflows, I use excel files from Sharepoint and others dataflows as sources.
When I try to refresh dataflow either I get null data nor miss-match data. But queries work well in query editor in both Desktop & Service.

I do multiple combining steps in the same query. And when I put the different applied steps in different queries, it seems to work. So I think the issue come from the Merge/Append steps but i don't know why or if this is really the cause of the problem, it remains a hypothesis.

I specify that it worked perfectly two months ago with the same queries. I had no problem updating dataflows. And the queries work in the query editor. The problem occurs when I launch the dataflow by clicking on the refresh button.

Has anyone else had this kind of problem ? May be this is due to updates to the Power BI Service (dataflow) on the Microsoft side.

Thank you !!

[v-deddai1-msft]

Hi @Anonymous ,

What's the detailed error message when you refresh the dataflow? And Did the it refreshes well in power bi desktop?

Best Regards,

Dedmon Dai

[Anonymous]

Hi @v-deddai1-msft ,

I have sometime "can't convert null in Logical Type", but this is due to null data because of miss-match. And yes it refreshes well in Power BI Desktop.

Best regards,

[v-deddai1-msft]

Hi @Anonymous ,

Did you contain any null result in the condition of if forumula in m-query as mentioned in https://stackoverflow.com/questions/35904951/power-query-m-we-cannot-convert-the-value-null-to-type-logical/35905223. 

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

Best Regards,

Dedmon Dai