Query oracle user and password

Oracle is a widely used database management system for managing large databases. When using Oracle, a very important task is to manage database users and passwords. In this article, we will introduce how to query Oracle user and password.

Oracle User and Password

In Oracle, a user is an entity that has permission to access the database. Every Oracle user must have a unique username and password. Users can be assigned different permissions and roles, and can use these permissions and roles to access different objects in the database. Passwords are a user protection mechanism that ensures only authorized users can access the database.

Methods for querying Oracle users and passwords

There are many ways to query Oracle users and passwords. Two of the common methods are introduced below.

1. Query the sys.user$ table

The sys.user$ table is one of the system tables used by Oracle to store user information. This table contains the details of all Oracle users, including username, password and some metadata. You can use the following SQL query to query the user name and password in the sys.user$ table:

SELECT name,spare4 FROM sys.user$;

This query will return sys.user All usernames and passwords in the $table. Among them, the name column contains the username, and the spare4 column contains the hash value of the password. A hash is an irreversible form of encryption that can be used to verify a user's password as long as the hash is saved in the database.

It should be noted that before using this method to query user passwords, please obtain administrator rights, otherwise you will not be able to query the sys.user$ table.

2. Using Oracle built-in functions

Another way to query Oracle users and passwords is to use Oracle built-in functions. There are multiple functions in Oracle database that can be used to query user and password information, such as the DBMS_METADATA.GET_DDL and DBMS_METADATA.GET_DEPENDENT_DDL functions.

Specifically, you can use the following SQL query statement to obtain user and password information:

SELECT username,password FROM dba_users;

As you can see, this query statement is faster than The previous way is easier to understand. It uses the built-in Oracle function dba_users to obtain all user and password information in the database and returns a result set containing usernames and passwords.

It should be noted that for this method of query, you need to have dba_users system permissions, otherwise you will not be able to successfully obtain user and password information.

Conclusion

Querying Oracle users and passwords is one of the most common tasks in database administration. Through the two methods introduced above, you can easily query user and password information in Oracle, and you can choose which method to use according to your specific needs. Whether you are managing a production database or testing or learning Oracle, these methods will provide you with useful query options to help you better manage your Oracle database.

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