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geirselvag
Frequent Visitor

Dynamic Column Expand

Hi Folks,

 

I get error message when trying to dynamically expand columns.  When doing manuell column expand, the step is working but the content will change over time. The underlying data include record type, so there's a need to further expand these and unpivot the fields.

Would appreciate any tips and suggestion.

PowerQuery - dynamic column expand.png

 




Thanks!
GS 

2 REPLIES 2
jennratten
Super User
Super User

Hello - without seeing a preview of the table it's hard to say for sure, but I would guess your table is returning some null records instead of list records, which cannot be expanded without first converting the values. Can you please confirm whether or not this is indeed the case?  At the RemovedColumns step, pls click the whitespace next to the first record object in the column (since in your screenshot it looks like that is one throwing an error).  Can you please post a snip of what you see in the preview when you do that?

 

@jennratten, thank you for you feedback. The underlying data, is nested records.

Dyn_ExpCols_M4.png

The structure after the 2nd underlying record (columns) is not dynamic - but has fixed columns (ref. Exp_Value, Exp_assingedBy, Exp_user). Therefore only looking for dynamically expand the first column ("assingments" - user id) with records, that also generate null values (ref. photo) because keep taskId reference.

The M Power Query, is working but based on manuall step by step configuration. The issue start when a new assignment is created, so that have to re-run the manual expand columns process.

Dyn_ExpCols_M2.png
  
Dyn_ExpCols_M3.png

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