Oracle db linked to Ms access(.mdb)

I have a report that links a "oracle command" from an oracle 10g db to a ms access(.mdb) table.

The report runs very very slowly. still running after 2.5 hours....:-)

The command when run by itself returns about 290k records and completes in about 35 mins, and the ms access table has 75k records and complets in about 5 mins.

I am using the ms table as a lookup/insert, when a field in the oracle table returns an unknown value.

The oracle command pulls in about 50 fields, and the ms table is 3 fields.

i am guessing all the data from both sources is being pulled in ?, and then the link is being done in memory or temp disk space, so hence the lonnnnnnng delay ?

any suggestions how i could speed this up ?