where clause and OR

[Anon]

Is there some problem I am overlooking for the following SELECT statement? When I run the script using the AND in the WHERE clause, I get my results quickly. When I run the exact same script replacing the AND for an OR in the WHERE clause, it bogs down and does nothing. Here is my Select Statement using the OR:

select
nchamps_rec.type AS national,
conferences.longname AS conference

from nchamps_rec, cchamps, conferences

where (nchamps_rec.team = '$team'
and nchamps_rec.year = $year1)

OR (nchamps_rec.team = cchamps.teamid
and nchamps_rec.year = cchamps.year
and cchamps.confid = conferences.conid)

");

[tomhath]

When you have the OR, there are no conditions on the three way join of the tables involved, so it should return a lot of rows:
(#rows in nchamps_rec #rows in cchamps #rows in conferences)

Sometimes called the cartesian product of the tables.

[Anon]

I see what you are saying. I need to treat the OR statement as a stand alone. Thanks for the response.

David