跨库访问-dblink
一.创建数据库:tiger和java数据库
二.场景:在tiger库中访问java库中emp表的数据
1.查看dblink: 看是否有tiger库的dblink
select * from dba_db_links;
2.在tiger库中创建db_link:
create public database link #LINK_NAME# connect to #USRNAME # identified by #PASSWORD# using
(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = XXX.XXX.XXX.XXX)(PORT = 1521))
(CONNECT_DATA =(SERVER = DEDICATED)(SERVICE_NAME = XXX))
)';
LINK_NAM为自定的名称;
USERNAME和PASSWORD为指定的oracle数据库中的用户名和密码,
SERVICE_NAME如果不确定的话,可以通过以下语句获得:
select name,value from v$parameter where name='service_names'
3.在tiger库中查询java库中emp表数据
select * from emp@LINK_NAME
4.删除db_link
drop public database link LINK_NAME