CurtHagenlocher commented on issue #3134: URL: https://github.com/apache/arrow-adbc/issues/3134#issuecomment-3062332255
I'm curious about how this works for the Dremio ODBC driver (either with or without Flight); does it wait until it's read all the chunks before it reports the schema of the result set? The only somewhat-analogous thing I've seen is with Snowflake `NUMBER(N, 0)` columns where an Arrow-formatted data chunk might be represented as a number of lower precision. But the reported schema always contains the maximum precision and so the driver just needs to cast columns in individual chunks in order to assemble the final output. (And there's no FlightSQL in this picture; just Arrow-formatted data.) There's also some overlap with schema evolution in formats like Delta, where columns in the individual Parquet files don't have to match exactly the declared schema of the table. But they do have to be compatible with it, so a table with an `int` column can't have a Parquet file where that column is an `int64`. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: github-unsubscr...@arrow.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
