Oracle Database Administration: The Essential Refe

Choosing the name

Before you create an Oracle database, you must choose a name for it as well as for the Oracle instance which will mount and open it. We recommend that the database name and the instance name be the same, unless you are running Oracle Parallel Server. In that case, we recommend choosing a database name and appending the instance number to it to form a unique name for each instance. For more information about the database and the instance, see Chapter 10, and Chapter 11.

While the names can be somewhat arbitrary, it is usually best to choose meaningful names—this will pay dividends later. The instance name must be unique on the host machine (that is, if you run more than one Oracle instance on a single machine, each must have a different name) for the following reasons:

• Oracle appends the instance name to a standard prefix in order to create known filenames that are used by default. For example, the default name for the initialization file is created by adding the instance name to the prefix INIT. So, if the instance name is TEST, then Oracle will expect an initialization file called initTEST.ora (unless the pfile parameter is explicitly specified when starting the instance). The alert log filename is generated in a similar manner: the alert file for the TEST instance will be alert_TEST.log.

• On most platforms, the internal process names used for the background processes are created by appending the instance name to a standard process name. For example, the PMON process ...