测试条件: 假设某公司总部在北京,新疆有其下属的一个分公司。在本次测试中,新疆的计算机为本地计算机,即本要的IP地址
测试条件:
假设某公司总部在北京,新疆有其下属的一个分公司。在本次测试中,新疆的计算机为本地计算机,即本要的IP地址为:192.168.1.100
北京的总部有一个集中的数据库,其SID是SIDBJ,用户名:userbj,密码:bj123,北京的IP地址是:192.168.1.101。
在本地(新疆)的分公司也有一个数据库,,其SID是SIDXJ,用户:userxj,密码:xj123,新疆的IP地址是:192.168.1.100。
要将本地新疆的SIDXJ数据库中访问到北京的数据库SIDBJ中的数据。
也就是说,在sidxj的数据库中,用户userxj(192.168.1.100)需要建立DBLINK,以userbj的用户身份访问sidBJ(192.168.1.101)中的数据。
测试环境:两个数据库均建立在WINXP上,Oracle的版本均为Oracle817
建立环境时,要注意关闭两台计算机上的Windows的防火墙,否则,会出现能ping通,但Oracle连接不通的情况。
1、问:如何返回数据库的GLOBAL_NAME?
执行SELECT * FROM GLOBAL_NAME;
北京的数据库的GLOBAL_NAME为SIDBJ.US.ORACLE.COM
新疆的数据库的GLOBAL_NAME为SIDXJ
2、问:如何查看Global_name参数是true还是False?
答:执行:SQL> show parameter global_name;
执行的结果如下:
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
global_names boolean TRUE
表示该参数是true.
该参数为true时,你在本地建立的DBLINK的名称必须和远程的Global_name一致才行。
3、问:查看远程数据徊是否支持高级复制功能。
答:通过查看v$option视图,如果其中Advanced replication为TRUE,则支持高级复制功能;否则不支持。
执行语句为:select * from v$option;
也可以执行select * from v$option where PARAMETER='Advanced replication'语句,
如何返回值为True,那么就是支持,否则就是不支持。在两个数据库中都是检查是否支持才行。
建立步骤:
1、在本地建立一个Oracle的客户端连接tns_xj_to_bj,用于连接北京的数据库。
在北京的数据库中,建立一个表用于测试。
create table USERBJ.BJ_TEST
(
STU_ID NUMBER,
STU_NAME VARCHAR2(100)
)
在其中增加一条记录:
insert into BJ_TEST (STU_ID, STU_NAME)
values (1, '钟德荣');
2、新建一个连接tnsxj,用于连接本地的sidxj数据库,以tnsxj/userxj/xj123登录到PLSQL中。
下面开始创建连接到北京的远程数据连接DBLink。
create database link SIDBJ.US.ORACLE.COM connect to userbj identified by bj123 using 'tns_xj_to_bj';
其中:SIDBJ.US.ORACLE.COM是远程的数据库的global_name,userbj是连接SIDBJ的用户名,bj123是userbj的密码,
tns_xj_to_bj是本地建立的连接到北京的数据库的服务名。
3、测试连接是否成功:
select * from dual@SIDBJ.US.ORACLE.COM
如果返回结果如下则表示连接成功了。
DUMMY
-----
X

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