Oracle中使用同义词
一、背景 有两个sid:Asid,Bsid,在Asid下有两个用户Auser1,Auser2,在Bsid下有一个用户Buser1。其中Auser2和Buser1建立了dblink。现希望通过登录Buser1访问Auser1上的三张表table1,table2,table3信息和函数function1。 二、步骤 ①登录Auser1对Auser2授
一、背景
有两个sid:Asid,Bsid,在Asid下有两个用户Auser1,Auser2,在Bsid下有一个用户Buser1。其中Auser2和Buser1建立了dblink。现希望通过登录Buser1访问Auser1上的三张表table1,table2,,table3信息和函数function1。
二、步骤
①登录Auser1对Auser2授权(若需要删除则加上delete)
grant insert,select,update on table1 to Auser2;
grant insert,select,update on table2 to Auser2;
grant insert,select,update on table3 to Auser2;
grant execute on function1 to Auser2;
②登录Auser2建立同义词
create synonym table1 for Auser1.table1;
create synonym table2 for Auser1.table1;
create synonym table3 for Auser1.table1;
create synonym function1 for Auser1.function1;
③登录Buser1查找db_link名(例如查出来的db_link名为mydblink1)
select username,db_link from user_db_links
④建立Buser1的同义词
create synonym table1 for Auser2.table1@mydblink1;
create synonym table2 for Auser2.table2@mydblink1;
create synonym table3 for Auser2.table3@mydblink1;
create synonym function1 for Auser2.function1@mydblink1;
⑤测试
此时登录Buser1通过select * from table1就可以访问table1了。
三、注意点
也可以建立procedure的同义词,但是这样执行的过程中不允许commit。如果要提交的话请在如JDBC中commit()。

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