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某些情况下:我们希望在一个sqlserver下访问另一个sqlserver数据库上的数据,或者访问其他oracle数据库上的数据,要想完成这些操作,我们首要的是创建数据库链接。
数据库链接能够让本地的一个sqlserver登录用户映射到远程的一个数据库服务器上,并且像操作本地数据库一样。那么怎么创建数据库链接呢?我现在有两种方法可以实现。
第一种:在 sqlserver 企业管理器中,建立,这个比较简单的,首先在 安全性--〉数据库链接 上点右键 ,在出现的菜单中点 新建数据库链接 ,然后会弹出一个界面,需要我们填写的有:链接服务器(这是一个名字,自己根据情况自行定义,以后就要通过他进行远程访问了),提供程序名称(这个就是选择数据驱动,根据数据库类型来选择,不能乱选,否则链接不上的),数据源(对于sqlserver就是远程数据库服务器的主机名或者IP,对于 oracle 就是在 oracle net config 中配置的别名),安全上下文用户和口令(也就是远程服务器的用户和口令)。
第二种:利用系统存储过程
创建一个sqlserver对sqlserver的数据库链接:
exec sp_addlinkedserver 'link_northsnow','',
'SQLOLEDB','远程服务器主机名或域名或ip地址'
exec sp_addlinkedsrvlogin 'link_northsnow','
false',null,'用户名','用户口令'
创建一个sqlserver对Oracle的数据库链接:
exec sp_addlinkedserver 'link_ora', 'Oracle',
'MSDAORA', 'oracle数据库服务器别名'
exec sp_addlinkedsrvlogin 'link_ora',
false, 'sa', '用户名', '用户口令'
有了数据库链接我们就可以使用了。对于sqlserver和oracle中的使用方法是有区别的。
对于sqlserver:
create view v_lhsy_user as select * from link_northsnow.lhsy.dbo.sys_user
select * from v_lhsy_user
其中lhsy为远程的数据库名
sys_user为表名
对于oracle:
create view vvv as select * from
link_ora..NORTHSNOW.SYS_USER
select * from vvv;
其中northsnow为远程oracle数据库服务器的一个用户名,SYS_USER为该用户在该服务器上的一个表,要非常注意的是:数据库链接(link_ora)后面有两个点(..),再往后面必须全部大写,查询的对象一般为表格或者视图,不能查询同义词。
要想删除数据库链接,也有两种方法,
一种方法是在企业管理器中操作。
另一种是用系统存储过程:
exec sp_dropserver
数据库链接名称,'droplogins' 。
数据库链接能够让本地的一个sqlserver登录用户映射到远程的一个数据库服务器上,并且像操作本地数据库一样。那么怎么创建数据库链接呢?我现在有两种方法可以实现。
第一种:在 sqlserver 企业管理器中,建立,这个比较简单的,首先在 安全性--〉数据库链接

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