Re: Re[2]: Re[2]: Migrating from 7.31 to 9.20

Hi RAM, >Hi Tony > >I will appreciate your facts. > >We manage huge databases ranging from 500GB to 1.5 terrabytes. During >the >database design phase phsyical as well as logical disk >organization is >done to balance I/O .. etc. Do you mean to say that this IO will remain balance for the life of the system? If you initially have one extent for a table, won't the no. of extent increase with the table growth? All systems do need reorganisation once a while to maintain the system performance. > >No 24x7 buisness can afford couple of days down time + disk just for > >migrating from 7.31 to 9.20. ( if dbexport is the way to go ..) I > >guess this ( dbexport method ) could be one of reasons why many > >installations are not migrating to a latest verison. I think you misunderstood, you don't need to do dbexport/import while upgradation, its only if you have any problems like 1] More no. of extents 2] Unbalanced IO etc. Dbexport/import can solve these problems. You can always do upgradation without doing any dbexport/import. Rather you don't need to touch the data with any of the migration utilities. You can easily do the upgradation in following steps : Bring existing instance offline. Install new version Set/Change Environment/Config parameters Bring the (new version)server online Run oncheck Run update statistics Take zero level backup > >My approach would be to go for migration by retaining existing data > >structures in case of huge databases. What do you mean by retaining existing data structures? Do you mean if you don't do dbexport/import you retain existing disk structures? >You get the performance benefit of the server >architecture and at the same time not locked in cat-4 products. Do you mean dbexport/import will harm the system performance? >I hope informix >will continue to support backward compatibility on storage structures. You can get more info on this in the Migration GUIDE. CHEERS ????? tONY >____________________Reply Separator____________________ >Subject: Re: Re[2]: Migrating from 7.31 to 9.20 >Author: "Tony Woods" <twoods786@hotmail.com> >Date: 7/12/00 11:46 PM > >Hi Ram, > >I think they are asking to do the dbexport, dbimport as you get an >opportunity to solve the problems as below : >--Tables having more no. of extents >--Placing tables properly to balance IO to chunks/dbspaces > >Dbexport, Dbimport is not a requirement but if you can afford the downtime >to do it, I would surely do it as it will tremendously improve the system >performance and also allow disk reorganisation. > >And also there are changes in the storage structures and Informix will do >it >automatically when you do oninit for the first time after upgradation. It >will also rebuild the sysmaster and sysutils database in that process. > >Cheers !!!!! > >Tony > > > >From: Ram.Mohan.Kompella@banctec.com > >To: "David Weis" <dweis@louisville-i-market.com>, informix-list@iiug.org > >Subject: Re[2]: Migrating from 7.31 to 9.20 > >Date: Tue, 11 Jul 2000 15:38:12 -0500 > > > >Hello everybody > > > >I am in the database world for the last 5 years working on Informix ( as > >well > >as O and S ) > > > >Is any body sure out there that there are changes in storage data > >structures > >from 7.31 to 9.20 ? > >dbexport and dbimport is okay for small databases. What if the Database > >size is > >a Terrabyte and above. I do not think Informix can afford recommend > >'dbimport' > >and 'dbexport' as a practical solution. > > > >Any ideas ??? > > > >Ram > >____________________Reply Separator____________________ > >Subject: Re: Migrating from 7.31 to 9.20 > >Author: "David Weis" <dweis@louisville-i-market.com> > >Date: 7/10/00 8:54 AM > > > > > >Obnoxio The Clown wrote in message <8kc48c$jp6$1@news.xmission.com>... > > > > > >From: dins dins <dins_d@yahoo.com> > > >> > > >>So, which way would be better to ugrade database from > > >>IDS 7.31 to IDS 9.20? > > >> > > >>1) To take backups from database, go to Quiescent mode > > >>and install new version over older? > > >> > > >>OR: > > >> > > >>2) install 9.20, take dbexport from IDS 7.31 and > > >>import it to 9.20? > > > > > >Call me old fashioned, but I prefer 2). Also, I don't think 1) will >work, > >I > > >think you have to first revert to 7.30 then upgrade to 9.20. I could be > > >wrong, though. Oh, and going Quiescent will probably not work anyway -- > >you > > >can't overwrite a file that's in use, IIRC. > > > >I guess I am old fashioned, too. I prefer exporting the data and then > >importing it to the new version for all upgrades --- guess I find too >many > >cases where there is bad data (ugh!) or many tables with MULTIPLE extents > >to > >even try an in-place upgrade. > > > >David Weis > >Louisville, KY USA > >dweis@louisville-i-market.com > >Voice: 502-637-7316 > > > > > > > > > >________________________________________________________________________ >Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com > ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com