I'm trying to actually run the experiments Tom suggested running EXPLAIN on
the DBT3 DSS queries for various default_stats_target sizes. It's a bit of a
headache because DBT3 seems to be unmaintained these days so lots of things
don't really work.
I ran into an error I've never seen before:
ERROR: XX000: could not devise a query plan for the given query
LOCATION: set_cheapest, pathnode.c:191
I haven't tried to figure out what's going on yet.
The schema is attached and the query which triggers the error is:
explain select
s_name,
count(*) as numwait
from
supplier,
lineitem l1,
orders,
nation
where
s_suppkey = l1.l_suppkey
and o_orderkey = l1.l_orderkey
and o_orderstatus = 'F'
and l1.l_receiptdate > l1.l_commitdate
and exists (
select
*
from
lineitem l2
where
l2.l_orderkey = l1.l_orderkey
and l2.l_suppkey <> l1.l_suppkey
)
and not exists (
select
*
from
lineitem l3
where
l3.l_orderkey = l1.l_orderkey
and l3.l_suppkey <> l1.l_suppkey
and l3.l_receiptdate > l3.l_commitdate
)
and s_nationkey = n_nationkey
and n_name = 'IRAQ'
group by
s_name
order by
numwait desc,
s_name;
--
greg
