Well, no doubt it varies by Oracle version, but my observations are that lob performance isn't very good. My personal, un-benchmarked observation is that lob io is takes between 2 and 4 times longer than IO on regular columns. Once again, I did not perform a test on this, its strictly a personal observation primarily based on imp/exp experience. On Mon, Aug 23, 2010 at 6:06 AM, Leyi Zhang (Kamus) <kamusis@xxxxxxxxx>wrote: > so ... how about MOS note "*LOB Performance Guideline [ID 268476.1]" ?* > > > -- > Kamus <kamusis@xxxxxxxxx> > > Visit my blog for more : http://www.dbform.com > Join ACOUG: http://www.acoug.org > > > On Mon, Aug 23, 2010 at 6:20 PM, Kenneth Naim <kennethnaim@xxxxxxxxx>wrote: > >> Yes, I have. I’m looking for something more definitive, less theory and >> more application. >> >> >> >> Thanks, >> >> Ken >> >> >> >> *From:* Leyi Zhang (Kamus) [mailto:kamusis@xxxxxxxxx] >> *Sent:* Monday, August 23, 2010 2:34 AM >> *To:* kennethnaim@xxxxxxxxx >> *Cc:* oracle-l@xxxxxxxxxxxxx >> *Subject:* Re: Lob Performance >> >> >> >> Have you read online doc: *Oracle® Database SecureFiles and Large Objects >> Developer's Guide* >> * >> http://download.oracle.com/docs/cd/E11882_01/appdev.112/e10645/adlob_performance.htm#i1007089 >> >> *-- >> Kamus <kamusis@xxxxxxxxx> >> >> Visit my blog for more : http://www.dbform.com >> Join ACOUG: http://www.acoug.org >> >> On Mon, Aug 23, 2010 at 6:01 AM, Kenneth Naim <kennethnaim@xxxxxxxxx> >> wrote: >> >> I haven't dealt with lob performance much. Can someone point to a good >> site >> or whitepaper how to measure lob size, test and improve (b)lob >> performance. >> I'm checking google and mos and haven't found a comprehensive article. >> >> Thanks, >> Ken >> >> >> -- >> //www.freelists.org/webpage/oracle-l >> >> >> > > -- Andrew W. Kerber 'If at first you dont succeed, dont take up skydiving.'