oracle 10gR2 dataguard db_unique_name parameter

DB_UNIQUE_NAME[color=rgb(34,34,34)][backcolor=rgb(255,255,255)]Specifies a unique name for the database at this destination.[color=rgb(34,34,34)][backcolor=rgb(255,255,255)][table=98%]
CategoryDB_UNIQUE_NAME=name
Data TypeString
Valid valuesThe name must match the value that was defined for this database with the [font=新宋体]DB_UNIQUE_NAME parameter.
Default valueNone
Requires attributes ...None
Conflicts with attributes ...None
Corresponds to ...[font=新宋体]DB_UNIQUE_NAME column of the [font=新宋体]V$ARCHIVE_DEST view

[color=rgb(34,34,34)][backcolor=rgb(255,255,255)][font=Tahoma, sans-serif]Usage Notes[list]
This attribute is optional if:[list]
[*]The [font=新宋体]LOG_ARCHIVE_CONFIG[font=新宋体]=DG_CONFIG initialization parameter is not specified.
[*]This is a local destination (specified with the [font=新宋体]LOCATION attribute).
[*]This attributes is required if the [font=新宋体]LOG_ARCHIVE_CONFIG=DG_CONFIG initialization parameter is specified and if this is a remote destination (specified with the[font=新宋体]SERVICE attribute).
[*]Use the [font=新宋体]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 [font=新宋体]DB_UNIQUE_NAME must match one of the [font=新宋体]DB_UNIQUE_NAME values in the [font=新宋体]DG_CONFIG list. Redo transport services validate that the[font=新宋体]DB_UNIQUE_NAME attribute of the database at the specified destination matches the [font=新宋体]DB_UNIQUE_NAME attribute or the connection to that destination is refused.
[*]The name specified by the [font=新宋体]DB_UNIQUE_NAME attribute must match the name specified by the [font=新宋体]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.