The account that accesses the Oracle database has SYSTEM tablespace as the temporary tablespace which is never a good idea. Please ask the database administrator to assign a temporary tablespace other than SYSTEM which is large enough to take care of the sorting associated with the query.

Regarding the last problem - please paste the exact query and error message so that we can take a look at that. There is definitely something wrong on your side otherwise the query would not fail.

Thanks.

Syed