From: Randy DeWoolfson Subject: Re: Database Performance Date: 2000/07/07 Message-ID: <3965FCFB.5A6B149F@euclidsys.com>#1/1 Content-Transfer-Encoding: 7bit References: <39570A25.33DB2FBC@hotmail.com> <8j7ajb$1vf$1@nnrp1.deja.com> X-Accept-Language: en Content-Type: text/plain; charset=us-ascii X-Complaints-To: news@cais.net X-Trace: nnrp-corp.news.cais.net 962985142 80998 205.177.20.245 (7 Jul 2000 15:52:22 GMT) Organization: CAIS Internet Mime-Version: 1.0 NNTP-Posting-Date: 7 Jul 2000 15:52:22 GMT Newsgroups: comp.databases.oracle.server I also dont like to see more than 10 extents... Although I bet your performance is query related and not storage related... Randy sybrandb@my-deja.com wrote: > In article <39570A25.33DB2FBC@hotmail.com>, > kskasi@hotmail.com wrote: > > Hello everyone > > > > The problem is that, the biggest table we have in our system has got > > only about 50,000 records. But the system seems to be slow even with > > those many records. Our DBA feels that enough space wern't alloted to > > the tables and they might be sitting in multiple extends. I had a look > > at the extends and I did notice that there are about 7 - 10 extends for > > the big table and some of the indexes. According to him, if there are > > more number of extends then oracle has to search through all the extends > > which takes more time. I had a look at Oracle documentation and it > > dosen't mention about this at all. I just want a second opinion on this > > before I drop the tables and recreate them with enough space. I guess I > > can rebuild the indexes with enough space but the tables has to be > > dropeed and reloaded. Any help would be appreciated > > > > Cheers...kasi > > > > > > Searching through extents applies to full table scans and likely fast > full index scans. Oracle will never read more than one extent at a > time. IMO, have a fragmented index is much more harming your > performance than a table in a few extents, assuming you have infrequent > full table scans. > However, the critical limit is for me 10 extents. Whenever your object > has more, defragment it. > > Hth, > -- > Sybrand Bakker, Oracle DBA > > All standard disclaimers apply > ------------------------------------------------------------------------ > > Sent via Deja.com http://www.deja.com/ > Before you buy.