@WillBe Dremio (not for Parquet, ORC, AVRO) for MongoDB samples files for schema and if you have a column that is not part of those sampled files, you will not see them initially but you should be able to query the file that has that column ot query the entire collection and Dremio should do a schema learning
Dremio has internal schema via SQL where you can define your PDS, can you please try that approach, see documentation below
Dear Balaji, the behaviour of my collection was: Dremio ignored all the fields that had a null value. I had to fill in a value and do
alter table “<my_context>.table1” forget metadata
alter table “<my_context>.table1” refresh metadata
then the fields appeared.
As soon I set the fields to null and refresh the schema they dissappear again.
So I keep the fields filled in one dataset and everything is fine.
But I’ll try your solutione too and keep you informed if it works or not.
Many thanks for your support!