如何在Oracle里设置访问多个SQL Server数据库?假设我们要在Oracle里同时能访问SQL Server里默认的pubs和Northwind两个数据库。本文给出您答案。
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;
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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';
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(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)
访问SQL Server下数据库里的数据:
3、使用时的注意事项
ORACLE通过访问SQL Server的数据库链接时,用select * 的时候字段名是用双引号引起来的。例如:
create table stores as select * from stores@pubs;
select zip from stores;
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ERROR 位于第 1 行:
ORA-00904: 无效列名
select "zip" from stores;
zip
-----
98056
92789
96745
98014
90019
89076
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已选择6行,用SQL Navigator或Toad看从SQL Server转移到ORACLE里的表的建表。语句为:
CREATE TABLE stores
("stor_id" CHAR(4) NOT NULL,
"stor_name" VARCHAR2(40),
"stor_address" VARCHAR2(40),
"city" VARCHAR2(20),
"state" CHAR(2),
"zip" CHAR(5))
PCTFREE 10
PCTUSED 40
INITRANS 1
MAXTRANS 255
TABLESPACE users
STORAGE (
INITIAL 131072
NEXT 131072
PCTINCREASE 0
MINEXTENTS 1
MAXEXTENTS 2147483645
)
/
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总结:
Windows下Oracle9i网关服务器在$Oracle9i_HOME\tg4msql\admin目录下的initsqlserver_databaseid.ora。Windows下Oracle9i网关服务器listener.ora里面:
(SID_DESC=
(SID_NAME=sqlserver_databaseid)
(ORACLE_HOME=d:\Oracle\Ora92)
(PROGRAM=tg4msql)
)
Unix或WINDOWS下ORACLE8I,ORACLE9I服务器tnsnames.ora里面
northwind =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.2)(PORT = 1521))
)
(CONNECT_DATA =
(SID = sqlserver_databaseid)
)
(HS = sqlserver_databaseid)
)
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需要sqlserver_databaseid一致才行。
查看本文来源