DB_UNIQUE_NAME

Specifies a unique name for the database at this destination.

Category	DB_UNIQUE_NAME=name
Data Type	String
Valid values	The name must match the value that was defined for this database with the DB_UNIQUE_NAME parameter.
Default value	None
Requires attributes ...	None
Conflicts with attributes ...	None
Corresponds to ...	DB_UNIQUE_NAME column of the V$ARCHIVE_DEST view

Usage Notes

This attribute is optional if:
- The LOG_ARCHIVE_CONFIG =DG_CONFIG initialization parameter is not specified.
- This is a local destination (specified with the LOCATION attribute).
This attributes is required if the LOG_ARCHIVE_CONFIG=DG_CONFIG initialization parameter is specified and if this is a remote destination (specified with theSERVICE attribute).
Use the DB_UNIQUE_NAME attribute to clearly identify the relationship between a primary and standby databases. This attribute is particularly helpful if there are multiple standby databases in the Data Guard configuration.
The name specified by the DB_UNIQUE_NAME must match one of the DB_UNIQUE_NAME values in the DG_CONFIG list. Redo transport services validate that theDB_UNIQUE_NAME attribute of the database at the specified destination matches the DB_UNIQUE_NAME attribute or the connection to that destination is refused.
The name specified by the DB_UNIQUE_NAME attribute must match the name specified by the DB_UNIQUE_NAME initialization parameter of the database identified by the destination.

This 10g new parameter must be set differently for a standby from that of the primary even though their db_name's are the same.