Re: Massive Delete

Thanks for the link. And BTW, what you mean by "speed our partial database refreshes" J. normajeansebastian via DBMonster.com escribi': > http://www-306.ibm.com/software/data/informix/pubs/library/ids_94.html > scroll down and select the "Performance Guide, Version 9.4" > in this manual, go to chapter 9, "Fragmentation Guidelines". > > fragmenting by expression takes some prep work but once set up it really > simplifies massive deletes. > we use it to speed our partial database refreshes. > > good luck, > Norma Jean > > > > Tam OShanter wrote: > >>Yes. It does sound quite interesting. >>Can you provide more information, or at least a hint on where to start >>looking for practical examples? >> >>Thanks Friends, >> >>Tam. >> >>>...detach the fragment... >>> >> >>[quoted text clipped - 41 lines] >> >>>>Informix-list@iiug.org >>>>http://www.iiug.org/mailman/listinfo/informix-list > >

Hi Jean, Background: the application on top of my IDS manages logically different datasets. if that was confusing, here's the straight scoop. we run SAP. inside SAP one can define multiple clients. . Altho the SAP instance sees multiple clients, these client records are mixed in tables at DB level(informix). for example, if i have TABLEX, within this one table, the rows can represent multiple clients to SAP. so some of my big tables in informix i have fragmented by SAPclient#. Then we have an SAP refresh tool (from certified 3rd party vendor) that allows us to refresh a single SAP client within a database. For example refresh the production client into a test system (this also involves changing the client number but that's another story). so in my test system where i have IDS tables fragmented by SAPclient# (and lets say i have 4 SAP clients therefore my big tables have 4 fragments). Now we want to refresh client #2 from production data. THE STUFF YOU REALLY WANTED TO KNOW : because i have my big tables fragmented by client, i do not have to run a "delete from table where client# =2" which as you can imagine could take a long time..... the fact that i have fragmented my table by SAPclient# allows me to simply issue a detach statement for the fragment containing client#2, this makes the fragment a separate table. i can then drop that table. Now client#2 records are no longer in my table. i re-init the fragmentation strategy on the big table (thus adding the definition of client#2 into the proper fragment)....very fast. then i can load client#2 data back into the big table.... all while not impacting the other client records in the other 3 fragments of the table. i hope that made sense. it's fast as fast can be....... and didn't take that much to set up.... i love it Norma Jean. Jean Sagi wrote: >Thanks for the link. > >And BTW, what you mean by "speed our partial database refreshes" > >J. > >normajeansebastian via DBMonster.com escribió: >> http://www-306.ibm.com/software/data/informix/pubs/library/ids_94.html >> scroll down and select the "Performance Guide, Version 9.4" >[quoted text clipped - 21 lines] >>>>>Informix-list@iiug.org >>>>>http://www.iiug.org/mailman/listinfo/informix-list -- Message posted via http://www.dbmonster.com