I am using MonetDB for benchmarking on the TPC-H workload. I have successfully run queries 1, 3 and 10. However, when I try to run query 5:

select
         n_name,
         sum(l_extendedprice * (1 - l_discount)) as revenue
from
         customer,
         orders,
         lineitem,
         supplier,
         nation,
         region
where
         c_custkey = o_custkey
         and l_orderkey = o_orderkey
         and l_suppkey = s_suppkey
         and c_nationkey = s_nationkey
         and s_nationkey = n_nationkey
         and n_regionkey = r_regionkey
         and r_name = 'ASIA'
         and o_orderdate >= date '1994-01-01'
         and o_orderdate < date '1994-01-01' + interval '1' year
group by
         n_name
order by
         revenue desc;

it takes about two (2) hours to evaluate it. It is obvious that the query cannot be executed inside the main memory, so the system thrashes through paging. Still, this behaviour does not appear for the rest of the queries, as they are computed within one or two seconds. In all cases, the results are correct.

The specifications of my system are:

Processor: Intel Core 2 Duo @ 1.86 Mhz
RAM: 2 Gb
Operating System: Linux Ubuntu Gutsy 7.10
MonetDB version: Mserver5 (recently downloaded from your site).

Can you give me some indications about why this query takes too long and how can I bypass this response delay?
Thanks.