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> As there are no restrictions on the data
> being brought back what is wrong with
> doing a full table scan of each?
True there are no restrictions. The query is not going to return just one row where product number = 443. It's going to cover all of both tables it joins.
A simple unrestricted join of two tables will be faster if you just do a full table scan, you avoid the overhead of also looking at the indexes. But when SUM / GROUP BY are added this general rule doesn't apply and indexes will help significantly.
-- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Greg Moore INET: sqlgreg_at_pacbell.net Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).Received on Wed Sep 19 2001 - 15:07:44 CDT