Re: Question: Oracle Naming

On Thu, 4 Nov 1999 12:21:46 +0100, "Sex_appeal" <aa_at_aa.es> wrote:

>I have just realiced that global_name is diferent from db_name.db_domain.
>I thought that if I change db_domain in init.ora, global_name changes
>automatically.
>The question is: What are the diferences between this three parameters?
>* db_name identifies the database name within the machine (and should be
>unique in the same machine)
>* db_domain identifies the database domain (WHAT DOES IT MEAN???)
>* global_name identifies the database within all the machines
>
>Is this right? I have a great confusion...
>
>Thank you
>
>

global_name is determined automatically at instance creation only and STORED in the controlfile, and should be stored in listener.ora . Hence any change to db_domain will not reflect in the global name of the database.

The following rules seem to apply for the determination of the global_name:

If you want a non-default database name, you should specify in the db_name parameter in init.ora. If you specify a database in your create database command, that should be the same database name as in your init.ora (they should be the same when you start the database anyhow)
If you don't specify anything, db_name will be oracle. The db_domain parameter is also specified in init.ora. If you don't specify anything, this parameter is taken from your names.default_domain in sqlnet.ora.
If you don't have that parameter in sqlnet.ora, or you don't have a sqlnet.ora the db_domain will be world. This rules are from experience at a site, where I was having serious problems with global naming and default domains.

Now global_name is there to UNIQUELY identify the database in any network, usually the Internet.
You should use it, as soon as you have some sort of hierarchical network, for example you have two branch offices, both in a different DNS domain (VERY important) with the same name. You could also use this to differentiate between production, development and test databases (of course on different servers) as follows:

oracle_at_prod.aa.es
oracle_at_dev.aa.es
oracle_at_tst.aa.es

How to setup an Oracle network like this - you MUST use the Oracle Network Manager (or net8 assistant) to make sure you generate correct network configuration files - you MUST use DNS-adressing, hardcoded IP is not supported - you can change the global name by issuing alter database rename global_name to '<new database name>'

Hth,

Sybrand Bakker, Oracle DBA Received on Thu Nov 04 1999 - 08:26:29 CST