Fix https://github.com/delta-io/delta/issues/1978

[dominikpeter]

Which Delta project/connector is this regarding?

• Spark
• Standalone
• Flink
• Kernel
• Other (Power BI)

Description

Fix #1978

How was this patch tested?

With local Power BI and sample Dataset

Does this PR introduce any user-facing changes?

No

[dominikpeter]

I tried to change the PowerBI_Delta.pbit file too. However, I don't think I am able to do it as I don't have the credentials for the Azure Storage Account used in the template.

@gbrueckl could you take a look at this?

[gbrueckl]

Hi @dominikpeter,
while the file fn_ReadDeltaTable.pq is the final output for Power BI, I usually also maintain the .pbit file for debugging and development of new features. It should be OK to just save the PQ queries in the template and save it without applying the changes.

regarding your change, the fix seems reasonable as the Extension column seems to contain everything after the first . found in the filename which was not an issue until the compacted files were introduced
However, instead of Text.Mid() I would rather use Text.EndsWith() (docs) which should be safer to use

If its OK for you, I would take over the ticket, do the changes in the PBIT and fn_ReadDeltaTable

regards and thanks for your contribution so far!
-gerhard

[dominikpeter]

@gbrueckl sure, you can take it over. Thanks a lot.

[dominikpeter]

@gbrueckl I am not sure how you want to use Text.EndsWith() as the compacted file also end with .json.

[gbrueckl]

I created a new PR that fixes this issue
#2101

I also added some documentation for further contributions under /connectors/PowerBI/README.md
Further I changed the sample data to use the Golden Tables provided as part of this repo wherever possible

[dominikpeter]

Will be solved here: #2101