Error ingesting json files in warehouse table

A final update for now at least: Microsoft has confirmed this is a bug, they hope to fix in the 1st quarter of 2026.

In the mean time they suggest to ingest it as a string and than use a notebook to parse the json array back into its original columns, or change the source, which for us wasn't an option.

Since it took ages for them to got to this stage I had already figured out I could use a notebook to read the json files in the lakehouse, read them into a dataframe, and when all files were read, write that dataframe to a table, in my case with an option "overwrite" since this is just a raw staging table.

Final kicker: They want me to give permission to archive the case (no doubt because of their KPI's), but the bug is not registered on MS's known issue list. I want them to document it there, but they for some reason don't want to do that, they want to keep it internal, so now my Dutch stubberness is playing up . 

The python code was quite simple in the end, even though we had multiple nested arrays. I used co-pilot to do the heavy lifting for me since i had to alias about 30 columns since i had to put the data in an existing table and the names needed to match 

These are the libraries I needed:

 

Folder path to read json files

 

 

Exploding the main body of the json (just part of it, as example)

 

Thats it in a nutshell