PL/SQL连接oracle服务器的连接串的书写

如果建立数据库的实例的事用NAME，则连接串，如下所示：
ORCL =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.88)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = ORCL)
    )
  )
如果简历数据库的实例时用的是SID，则连接串如下所示：
TVTM =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.123)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SID = orcl)
    )
  )