Oracle11默认用户管理数据库的重要主体（oracle11默认用户）

Oracle11g is one of the most widely used relational database management systems in the world. It is famous for its flexibility and power, but it is also known to be complex and challenging for new users. One of the essential features of Oracle11g is the default users. These users are critical for managing the system and ensuring its security. In this article, we will explore the important subject of Oracle11 default users and how they impact the management of the database.

Oracle11g comes with several default users, which are created automatically during the installation process. These users serve vital roles and are necessary for mntning the database. The primary default users include:

1. SYS: The SYS user is the most powerful user in Oracle11g. It has access to all system privileges and can perform any operation on the database. The SYS user is responsible for the administration of the system, including creating and deleting databases, setting parameters and initializing the database instance.

2. SYSTEM: The SYSTEM user is created automatically during Oracle11g installation. It is created with the password that was set during installation. SYSTEM is the owner of several important system-level schemas that are used in the administration of the database.

3. DBSNMP: DBSNMP is a user account used by the Intelligent Agent component of Oracle Enterprise Manager. It allows remote monitoring and management of the instances on which it is installed. The DBSNMP account is used to collect performance metrics and to monitor the database.

4. OUTLN: The OUTLN user is created with every new database that is created in Oracle11g. It is used to d in the migration of an existing database to Oracle. OUTLN contns several system-level objects that can help streamline this process.

Each of the default users in Oracle11g has a unique set of responsibilities and privileges. Understanding these roles is critical for the proper management of the database. As an administrator, it is essential to know how to create and manage these users, as well as how they interact with the rest of the database.

Creating and managing default users in Oracle11g is relatively simple, with many options avlable through the graphical user interface (GUI) of Oracle Enterprise Manager. For example, if you need to create a new user with limited access, you could use the CREATE USER command, which allows you to assign specific privileges and roles to the user.

CREATE USER MyUser
  IDENTIFIED BY MyPassword
  DEFAULT TABLESPACE Users
  TEMPORARY TABLESPACE Temp
  QUOTA 100M ON Users
  PROFILE DEFAULT;

The above code creates a new user named “MyUser” with the password “MyPassword.” It assigns the user to the default tablespace and temporary tablespace, grants them a quota of 100MB, and applies the default profile.

In addition to creating and managing default users, it is also important to keep these users’ passwords secure. This can be accomplished by using complex passwords with a combination of uppercase and lowercase letters, numbers, and symbols. Additionally, it is essential to change passwords regularly and use password policies that ensure users are not reusing old passwords.

In conclusion, understanding the default users of Oracle11g is an essential part of managing any database. These users play critical roles in the administration of the system, and it is essential to know how to create and manage them effectively. By following best practices such as using complex passwords and changing them regularly, you can help ensure the security of your database and mntn its integrity over time.