access controll
1Privilgeges
?1) Database security:
? --System security
? --Data security
?2)System privileges:Caining access to the database
?3)Object privileges:manipulationg thee content of the database objects
?4)Schemas:Collections of objects ,such as tables,views,and sequences
2System Privileges
? . More than 100 privileges are available;
? . The database administrator has high-levle system privileges for tasks such as:
??? creating new user,removing user,removing tables,backing up tables
3 Creating user
?the dba creates users by using the create user statement
?create user user
?identified by password;
?e.g create user object scott
???? identified by tiger;
?SQL> create user testuser
? 2? identified by test;
User created
SQL> conn testuser/test@orcl2000
Not logged on
SQL> grant access session to testuser;
grant access session to testuser
Not logged on
SQL> conn digit_cc/digit_cc@orcl2000
Connected to Oracle9i Enterprise Edition Release 9.2.0.1.0
Connected as digit_cc
SQL> grant create session to testuser;
Grant succeeded
SQL> conn testuser/test@orcl2000;
Connected to Oracle9i Enterprise Edition Release 9.2.0.1.0
Connected as testuser
4 user System privileges
?once a user is created,the dba can grant specific system privileges to a user
?grant privilege[,privilege...]
?to user [,user|role,public...];
?DBA can grant a user specific system privileges
?grant create session,create table,create sequence,create view? to scott;
5 creating and granting privileges to role
' Create a role
? create role manager;
?.grant privileges to a role
? grant create table,create view to manager
?.Grant a role to user
? grant manager to kochar;
?
SQL> create role testrole;
Role created
SQL> grant create table,create view,create sequence to testrole;
Grant succeeded
SQL> grant testrole to testuser;
6 change your password
?you can change your password by using the alter user statement;
?alter user scott
?indetified by lion;
7 object privileges
?object privileges vary from object to object
?an owner has all the privilege to the object
?an owner can give specific privilege on that owner object
? grant select on auther to testuser;
? grant select on outher to testuser with grant option -- testuser also can grant it to
other user;
? grant update(department_name,location_id)
? on departments
? to scott,manager;
8 how to revoke object privileges
?--you use the revoke statement to revoke privileges granted to other users
?--privileges granted to other users through the with grant option clause are also revoked.
? revoke privilege {[,privilege...]|all} on object
? from {user[,user....]|role|public}
? [cascade constraints]
? revoke select on author from user;
9 Database Links
?Database link allow user to access data in the remote database;
SQL> create database link kjw1
? 2? connect to digit_cc identified by digit_cc
? 3? using 'orcl2000';
Database link created
SQL> select * from digit_cc.table_action@kjw1;
posted on 2006-09-29 15:40 康文 閱讀(240) 評論(0) 編輯 收藏 所屬分類: 數(shù)據(jù)庫