Yes, planning on doing a 10046 today. A MVGroup refresh does a merge. I'm sure about that. RF Robert G. Freeman Oracle Consultant/DBA/Author Principal Engineer/Team Manager The Church of Jesus Christ of Latter-Day Saints Father of Five, Husband of One, Author of various geeky computer titles from Osborne/McGraw Hill (Oracle Press) Oracle Database 11g New Features Now Available for Pre-sales on Amazon.com! BLOG: http://robertgfreeman.blogspot.com/ Sig V1.2 -----Original Message----- From: Zhu,Chao [mailto:zhuchao@xxxxxxxxx] Sent: Wednesday, August 22, 2007 1:16 AM To: robertgfreeman@xxxxxxxxx Cc: oracle-l Subject: Re: MView... Fresh build is much faster than Complete refresh... take a 10046 trace and do a compare. maybe it is doing a long delete before refresh, maybe truncate takes long... i think a single table refresh does the truncate , and refresh within a group does the delete. On 8/22/07, Robert Freeman <robertgfreeman@xxxxxxxxx> wrote: > > > So I have this materialized view. When I execute the create materialized > view command, it takes 32.39 seconds to build. A complete refresh (exec > dbms_mview.refresh('mview_name','C'); ) from the prompt > this takes almost 3-4 times longer. Does anyone have any thoughts on why > this might be so just right off hand. I've not run a 10046 on it yet, but I > thought maybe there is something about MVIEW Full Refreshes that I'm just > missing. > > RF > > > > Robert G. Freeman > Oracle Consultant/DBA/Author > Principal Engineer/Team Manager > The Church of Jesus Christ of Latter-Day Saints > Father of Five, Husband of One, > Author of various geeky computer titles > from Osborne/McGraw Hill (Oracle Press) > Oracle Database 11g New Features Now Available for Pre-sales on Amazon.com! > BLOG: http://robertgfreeman.blogspot.com/ > Sig V1.2 > -- Regards Zhu Chao www.cnoug.org -- //www.freelists.org/webpage/oracle-l