Apache Druid

Could you structure the map as a json object? `{"key1":"value1","key2":value2"...}`
If so, then yes, Nested column ingestion will columnarize and index each key and make them accessible through JSON_VALUE functions.

Actually, just looked it up. Protobuf is not yet supported for nested column ingestion. As of 25.0 it supports JSON, Parquet, Avro, &amp; ORC.

I was looking at the code, specifically at <https://github.com/apache/druid/pull/13546>. the code seems to be suggesting that nested column is supported for protobuf.
I tried ingesting a protobuf map and tried storing it in a column with type json, using druid 25.0. It seems to be working fine so far.

That’s great! We’ll have to adjust the docs.