Johan, There is no need to convert sysdate to a string and back to a data. I'm not sure what you mean by "calculate the previous 24 hours when a query is run and bump the time by 6 hours".
It looks like you are trying to retrieve all records that have a date/time within the last 18 hours - is this correct? if so, then your query would be: where event_date > (sysdate + 6/24) - 1 The default date format really has nothing to do with how the dates are stored within the database - they are all stored the same way. This means you can do simple date math like above. Hope this is what you are looking for. Tom Mercadante Oracle Certified Professional -----Original Message----- Sent: Tuesday, April 09, 2002 8:13 AM To: Multiple recipients of list ORACLE-L I need a where clause to ACCURATELY (down to the second) calculate the previous 24 hours when a query is run and bump the time by 6 hours (event_date is based on GMT). The default date format has been set to 'SYYYY-MM-DD HH24:MI:SS','NLS_CALENDAR=GREGORIAN'. I've tried the following: " where event_date > (to_date(substr(sysdate,0,22),'YYYY/MM/DD HH24:MI:SS') + 6/24) - 1". Any ideas? -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Johan Muller 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). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Mercadante, Thomas F 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).