RE: ORACLE - instance can only have one DB

Correct, I just asked the new Oracle guy here - one instance in Oracle can only have one Database -----Original Message----- From: owner-informix-list@iiug.org [mailto:owner-informix-list@iiug.org] On Behalf Of Gentsch, Sam Sent: Friday, May 21, 2004 6:18 PM To: Neil Truby; informix-list@iiug.org Subject: RE: ORACLE - instance can only have one DB Hmm, I am wondering if there is a terminology issue here. Informix instances can have more than one DB. Oracle instances have only one DB. (At least that is what they said in the Oracle DBA 101 class I went to years ago...so be kind if I am wrong) But you can also have multiple instances of Informix on the same box. Meaning multiple shared memory structures, different onconfigs/servernames...egads this is hard to explain in an email. Abanero, is this making sense? Do you have one Informix instance (memory, onconfig etc) with multiple DB's in it, or do you have multiple instances that each have their own collection of databases, etc in it? -----Original Message----- From: Neil Truby [mailto:neil.truby@ardenta.com] Sent: Friday, May 21, 2004 4:15 AM To: informix-list@iiug.org Subject: Re: ontape Info "Abanero" <abanero@supereva.it> wrote in message news:ad9fb198.0405202354.554fe1b4@posting.google.com... > "Neil Truby" <neil.truby@ardenta.com> wrote in message news:<2h47atF8lir0U1@uni-berlin.de>... > > You've backed up all databases in ONE instance - the instance defined by the > > INFORMIXSERVER environment variable of the session you used to execute the > > ontape utility. > > Thanks to all, just to understand, my informix database has 4 > instances, with command: > > ontape -s -L 0. > > I have backed up all databases in ONE nistance. This means if I > restore database from Tape I lose all instances and only one istance > are restore? No. You have backed up one instance. If you restore from that tape you will restore just that instance. The others will not be affected. In order to back up the other three instances, or restore them, you would need to set the INFORMIXSERVER environment variable to some other appropriate value. sending to informix-list ________________________________ << ella for Spam Control >> has removed 1108 Spam messages and set aside 555 Newsletters for me You can use it too - and it's FREE! www.ellaforspam.com sending to informix-list

On Mon, 24 May 2004 04:15:05 -0400, Dirk Moolman wrote: Ya, but just to muddy the waters, you can have multiple 'schemas' in a single Orable database/instance and the tables in one schema are not visible to a process connected to another schema. Sounds suspiciously like a separate database to me but with the system catalog overhead of all databases mixed together. Art S. Kagel > Correct, I just asked the new Oracle guy here - one instance in Oracle can > only have one Database > > > > > > -----Original Message----- > > From: owner-informix-list@iiug.org [mailto:owner-informix-list@iiug.org] On > Behalf Of Gentsch, Sam > > Sent: Friday, May 21, 2004 6:18 PM > > To: Neil Truby; informix-list@iiug.org > > Subject: RE: ORACLE - instance can only have one DB > > > > Hmm, I am wondering if there is a terminology issue here. > > > > Informix instances can have more than one DB. > > Oracle instances have only one DB. > > > > (At least that is what they said in the Oracle DBA 101 class I went to > > years ago...so be kind if I am wrong) > > > > But you can also have multiple instances of Informix on the same box. > > Meaning multiple shared memory structures, different > > onconfigs/servernames...egads this is hard to explain in an email. > > > > Abanero, is this making sense? > > Do you have one Informix instance (memory, onconfig etc) with multiple > > DB's in it, or do you have > > multiple instances that each have their own collection of databases, etc > > in it? > > > > -----Original Message----- > > From: Neil Truby [mailto:neil.truby@ardenta.com] > > Sent: Friday, May 21, 2004 4:15 AM > > To: informix-list@iiug.org > > Subject: Re: ontape Info > > > > > > "Abanero" <abanero@supereva.it> wrote in message > > news:ad9fb198.0405202354.554fe1b4@posting.google.com... > >> "Neil Truby" <neil.truby@ardenta.com> wrote in message > > news:<2h47atF8lir0U1@uni-berlin.de>... > >> > You've backed up all databases in ONE instance - the instance > > defined by > > the > >> > INFORMIXSERVER environment variable of the session you used to > > execute > > the > >> > ontape utility. > > > >> Thanks to all, just to understand, my informix database has 4 > >> instances, with command: > > > >> ontape -s -L 0.> > > >> I have backed up all databases in ONE nistance. This means if I > >> restore database from Tape I lose all instances and only one istance > >> are restore? > > > > No. You have backed up one instance. If you restore from that tape you > > will restore just that instance. The others will not be affected. > > In order to back up the other three instances, or restore them, you > > would > > need to set the INFORMIXSERVER environment variable to some other > > appropriate value. > > > > > > sending to informix-list > > > > > ________________________________ > > << ella for Spam Control >> has removed 1108 Spam messages and set aside 555 > Newsletters for me You can use it too - and it's FREE! www.ellaforspam.com > > sending to informix-list

Oracle has a rather different definition of a database to us. If I understand correctly, their nearest equivalent to an Informix database is a schema. A database in Oracle is more like our instance (though they have instances as well but I'm not sure how that differs from their database. And me reading for an OCP!) Andy "Dirk Moolman" <DirkM@mxgroup.co.za> wrote in message news:<c8schn$90e$1@terabinaries.xmission.com>... > Correct, I just asked the new Oracle guy here - one instance in Oracle can only have one Database