Citing Knowledgebase sources when using a large .csv file as a source instead of many individual .md files

I figured how to do exactly what I was looking to do in terms of citing sources with .md files stored in spaces buckets (https://www.digitalocean.com/community/questions/linking-to-source-documents), it’s actually quite easy if you just request the sources/context from the API. Now I have a new challenge. I would like to move to using a .csv file because I want to add columns of metadata next to the content so that the metadata and content is all unified in a single knowledge base.

The problem is that I was relying on the filename names, bucket names and directories to construct the original source. With a single large .csv file every source ends up as /bucketname/foldername/some_big.csv

Maybe the only solution is to create an individual .csv for each and every .md file. That is an OK solution but I was just curious if that would be the best practice or if there is a better way and if there is a way to accomplish it with a single large .csv

This may be useful for other projects as well since datasets are often provided as .parquet files which are easy to dump into a large .csv file.

(it would be great if knowledge bases had support for .parquet files directly)