CREATE PUBLIC DATABASE LINK sxst03（连接名称） CONNECT TO sxdznydfd（用户名） IDENTIFIED BY sxdznydfd （密码）USING
        '(DESCRIPTION =
            (ADDRESS_LIST =
              (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.3（数据库所在机子的名称或IP）)(PORT = 1521))
            )
            (CONNECT_DATA =
        (SERVICE_NAME = sxst（要连接数据库的SID）)
            )
          )'
      下面是查询时的写法，在表名后增加 @sxst03  (@加上上面建立的连接名称)
          
          select * from  sde.Table_Registry@sxst03 where table_name='N2007E2003140411000B00XJLYD'