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Redo Log Process

Here is the correct order:
  1. The redo entries are written to the redo log buffer. When a transaction issues a COMMIT or reaches a normal end of task, the entries are written to the online redo log files.
  2. The LGWR process takes the images from the log buffer and places them into the online redo log files.
  3. When Oracle switches redo log files, the old redo log file is copied to an archived redo log file system by the ARC0 process. The redo log file can then be overwritten by Oracle.
  4. As the archived redo log file system becomes full, a user-written process is invoked to copy the redo log files to tape for long-term storage.

Determining the Global Database Name

The global database name consists of the user-specified local database name and the location of the database within a network structure. The DB_NAME initialization parameter determines the local name component of the database name, and the DB_DOMAIN parameter, which is optional, indicates the domain (logical location) within a network structure. The combination of the settings for these two parameters must form a database name that is unique within a network.For example, to create a database with a global database name of test.us.acme.com, edit the parameters of the new parameter file as follows:
DB_NAME = test
DB_DOMAIN = us.ooportal.com

You can rename the GLOBAL_NAME of your database using the ALTER DATABASE RENAME GLOBAL_NAME statement.
However, you must also shut down and restart the database after first changing the DB_NAME and DB_DOMAIN initialization parameters and recreating the control files. Recreating the control files is easily accomplished with the command ALTER DATABASE BACKUP CONTROLFILE TO TRACE.

DB_NAME Initialization Parameter

DB_NAME must be set to a text string of no more than eight characters. During database creation, the name provided for DB_NAME is recorded in the datafiles, redo log files, and control file of the database. If during database instance startup the value of the DB_NAME parameter (in the parameter file) and the database name in the control file are not the same, the database does not start.