Hi Denham, Suggestion 1) Perhaps you may create an index for table_1 (col1,col2) and table_2 (col3,col4) Suggestion 2) Try SELECT col1,col2 FROM Table_1 WHERE (0=(select count(*) from table_2 where col3=col1 and col4=col2)) Hope it helps. Regds, Catherine
-----Original Message----- Sent: Wednesday, March 27, 2002 4:53 PM To: Multiple recipients of list ORACLE-L Hello List Is there anyone who can give me a solution to this problem. It is a sql that runs forever and I eventually have to kill it, both tables are large 500000 + rows. Is there perhaps a quicker more effecient way of doing this. SELECT col1,col2 FROM Table_1 WHERE (col1,col2) NOT IN (SELECT col3,col4 FROM Table_2); TIA Denham Eva Oracle DBA _____ This e-mail message has been scanned for Viruses and Content and cleared by MailMarshal - For more information please visit <http://www.marshalsoftware.com> www.marshalsoftware.com _____ -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: CHAN Chor Ling Catherine (CSC) INET: [EMAIL PROTECTED] 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: [EMAIL PROTECTED] (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).