如何在Oracle里设置访问多个SQL Server数据库？

     1、在安装了Oracle9i Standard Edition或者Oracle9i Enterprise Edition的windows机器上(IP:192。168。
  0。2), 产品要选了透明网关(Oracle Transparent Gateway)里访问Microsoft SQL Server数据库 ORACLE9I_HOMEtg4msqladmin下新写initpubs。
    ora和initnorthwind。ora配置文件。 initpubs。ora内容如下: HS_FDS_CONNECT_INFO="SERVER=SQLSERVER_HOSTNMAE; DATABASE=pubs" HS_DB_NAME=pubsHS_FDS_TRACE_LEVEL=OFF HS_FDS_RECOVERY_ACCOUNT=RECOVER HS_FDS_RECOVERY_PWD=RECOVER initnorthwind。
    ora内容如下: HS_FDS_CONNECT_INFO="SERVER=sqlserver_hostname; DATABASE=Northwind" HS_DB_NAME=Northwind HS_FDS_TRACE_LEVEL=OFF HS_FDS_RECOVERY_ACCOUNT=RECOVER HS_FDS_RECOVERY_PWD=RECOVER $ORACLE9I_HOMEnetworkadmin 下listener。
    ora内容如下: LISTENER = (DESCRIPTION_LIST = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192。
  168。0。2)(PORT = 1521)) ) ) ) SID_LIST_LISTENER = (SID_LIST = (SID_DESC = (GLOBAL_DBNAME = test9) (ORACLE_HOME = d:oracleora92) (SID_NAME = test9) ) (SID_DESC= (SID_NAME=pubs) (ORACLE_HOME=d:OracleOra92) (PROGRAM=tg4msql) ) (SID_DESC= (SID_NAME=northwind) (ORACLE_HOME=d:OracleOra92) (PROGRAM=tg4msql) ) ) 重启动这台做gateway的Windows机器上(IP:192。
    168。0。2)TNSListener服务(凡是按此步骤新增可访问的SQL Server数据库时，TNSListener服务都要重启动)。 2、Oracle8i，Oracle9i的服务器端配置tnsnames。
  ora, 添加下面的内容: pubs = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192。  168。
  0。2)(PORT = 1521)) ) (CONNECT_DATA = (SID = pubs) ) (HS = pubs) ) northwind = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192。
    168。0。2)(PORT = 1521)) ) (CONNECT_DATA = (SID = northwind) ) (HS = northwind) ) 保存tnsnames。
  ora后,在命令行下 tnsping pubs tnsping northwind 出现类似提示，即为成功: Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192。
    168。0。2) (PORT = 1521))) (CONNECT_DATA = (SID = pubs)) (HS = pubs)) OK（20毫秒） Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192。
    168。0。2) (PORT = 1521))) (CONNECT_DATA = (SID = northwind)) (HS = northwind))OK（20毫秒） 设置数据库参数global_names=false。
   设置global_names=false不要求建立的数据库链接和目的数据库的全局名称一致。  global_names=true则要求, 多少有些不方便。
     oracle9i和oracle8i都可以在DBA用户下用SQL命令改变global_names参数 alter system set global_names=false; 建立公有的数据库链接: create public database link pubs connect to testuser identified by testuser_pwd using ’pubs’; create public database link northwind connect to testuser identified by testuser_pwd using ’northwind’; (假设SQL Server下pubs和northwind已有足够权限的用户登陆testuser,密码为testuser_pwd)。