From deepakthapliyal@yahoo.com Thu, 16 Aug 2001 18:12:31 -0700 From: Deepak Thapliyal Date: Thu, 16 Aug 2001 18:12:31 -0700 Subject: Re: Delete followed by Select Count(1) - SLOW Message-ID: MIME-Version: 1.0 Content-Type: text/plain Hi Jonathan, Can you tell us a little bit more about delayed block cleanouts .. if you can Thx Deepak --- Jonathan Lewis wrote: > Apart from the comments other posters > have made about truncate and the HWM, > bear in mind that a scan after deleting 100,000 > rows would probably be doing a lot of > delayed block cleanout - resulting in plenty > of redo log, and possibly a lot of dbwr activity. > > Jonathan Lewis > > Seminars on getting the best out of Oracle > Last few places available for Sept 10th/11th > See http://www.jlcomp.demon.co.uk/seminar.html > > > > > -----Original Message----- > To: Multiple recipients of list ORACLE-L > > Date: 16 August 2001 21:46 > > > |I have a user that deleted all of the rows in a > table > |(i.e. 100,000), waited for it to complete, and then > |ran a SELECT COUNT(1) FROM . It took a few > |minutes for '0 rows' to be returned to the prompt. > The > |table has ~60 extents (128k ea.). Granted, the > number > |of extents is excessive but it's a development > |instance and this table is an exception. > | > > > -- > Please see the official ORACLE-L FAQ: > http://www.orafaq.com > -- > Author: Jonathan Lewis > INET: jonathan@jlcomp.demon.co.uk > > 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@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). __________________________________________________ Do You Yahoo!? Make international calls for as low as $.04/minute with Yahoo! Messenger http://phonecard.yahoo.com/ -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Deepak Thapliyal INET: deepakthapliyal@yahoo.com 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@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).