How to change user password in oracle database

Oracle database is one of the most widely used relational database management systems in the world. In the process of using Oracle database, we often need to change the password of the database user to ensure data security. This article will introduce how to change the Oracle database user password.

1. Log in to the Oracle database

First, we need to log in to the Oracle database with administrator privileges. The Oracle database uses SYS or SYSTEM user as the administrator user. We can log in using the following command:

  sqlplus / as sysdba

After entering the command, you will be asked to enter the administrator password. After entering the correct password, you can log in.

2. Find the user who needs to change the password

After logging in to the Oracle database, you need to find the user who needs to change the password. We can use the following SQL statement to query all users in the database:

  SELECT * FROM dba_users

If we only need to query a specific user, we can use the following SQL statement:

  SELECT * FROM dba_users WHERE username='用户名'

After querying that the password needs to be changed After selecting the user, we need to remember the USERNAME and USER_ID of the user.

3. Change Password

After confirming the user who needs to change the password, you can use the following SQL statement to modify the user's password:

  ALTER USER 用户名 IDENTIFIED BY '新密码';

Where, ' New password' is the new password we want to change to.

If you need to change the password to a password different from the previous password, you can use the following SQL statement to modify it:

  ALTER USER 用户名 IDENTIFIED BY VALUES '哈希值';

Where, 'hash value' is the hashed password generated by the Oracle database . We can use the following SQL statement to query the hash value of an existing password:

  SELECT password FROM dba_users WHERE user_id=用户ID;

Based on the hash value queried, we can use the hash value when modifying the password to ensure that the new password is different from the old password.

4. Exit the database

After changing the password, we can use the following command to exit the Oracle database:

  exit;

At this point, change the Oracle database user password The process is complete.

Summary

When using Oracle database, password security is very important. We often need to change database user passwords to ensure data security. To change the Oracle database user password, we need to log in to the database as an administrator, find the user whose password needs to be changed, and then use the ALTER USER command to change the password. After the password change is completed, we should exit the Oracle database in time to prevent unauthorized access.

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