Problems with Order by in 7.3.2.3?

We're running a 205GB data warehouse on Sun Solaris with Oracle 7.3.2.3.

I have a simple query which selects one column from a table with a where clause that
says WHERE IN another single table query. With NO order by on this SQL, I get 209
rows returned within 1/2 second. If I place an ORDER BY clause on the statement
and order by the single column that's being returned, I get nothing back for over 40 mins.!!!
(In fact, I give up and kill the query at that point).

I don't understand how adding the ORDER BY to a query that returns one column and
209 rows could trash the query, but it seems to be doing that on my database. When I
do explain plans on the query, both with and without the ORDER BY clause, the plan
seems to change (not including the fact that an extra step to do the sort is of course
added). This appears to be a bug to me, but I'm wondering if anyone else has come
across this problem.

The sort parameters are all tweaked pretty nicely on this database, but even if they weren't,
it doesn't seem that sorting 209 rows would be a problem even with fairly badly set
parameters.

Anyone come across anything like this??

Thanks,

Stephen A. Rodgers Received on Sat Jan 10 1998 - 00:00:00 CST