Very large queries with ODBC

I am trying to execute a query that will return 8 million rows. The next
query I will need will return 45 million rows.
I have useDeclareFetch enabled.

I've traced into the ODBC code, and it seems like previous rows are
never discarded. This makes large queries, i.e. ones where you will be
doing bulk processing for OLAP, impossible.

Is this a known bug? (Is it a bug at all or a feature of ODBC?)
Are there, or would there be, plans to correct it?
If so, what is the strategy?