Dataguard 主库与备库的Service_Name 不一致时，如何配置客户端TNSName

ORA11G_DG=
  (DESCRIPTION_LIST=
    (FAILOVER=on)
    (DESCRIPTION=
      (ADDRESS=(PROTOCOL = TCP)(HOST = 192.168.202.136)(PORT = 1521))
      (CONNECT_DATA=
         (SERVICE_NAME=ORA11G)
      )
    )
    (DESCRIPTION=
      (ADDRESS=(PROTOCOL = TCP)(HOST = 192.168.202.137)(PORT = 1521))
      (CONNECT_DATA=
         (SERVICE_NAME=ORASTAND)
      )
    )
 )