6.3.5 Assigning Account Passwords

Required credentials for clients that connect to the MySQL server can include a password. This section describes how to assign passwords for MySQL accounts. Client authentication occurs using plugins; see Section 6.3.7, “Pluggable Authentication”.

MySQL stores passwords in the user table in the mysql database. Operations that assign or modify passwords are permitted only to users with the CREATE USER privilege, or, alternatively, privileges for the mysql database (INSERT to create new accounts, UPDATE to modify existing accounts). If the read_only system variable is enabled, use of account-modification statements such as CREATE USER or SET PASSWORD additionally requires the SUPER privilege.

To assign a password when you create a new account with CREATE USER, include an IDENTIFIED BY clause:

mysql> CREATE USER 'jeffrey'@'localhost'
    -> IDENTIFIED BY 'mypass';

CREATE USER also supports syntax for specifying the account authentication plugin. See Section, “CREATE USER Syntax”.

To assign or change a password for an existing account, one way is to issue a SET PASSWORD statement:

    -> 'jeffrey'@'localhost' = PASSWORD('mypass');

If you are not connected as an anonymous user, you can change your own password by omitting the FOR clause:

mysql> SET PASSWORD = PASSWORD('mypass');

The old_passwords system variable value determines the hashing method used by PASSWORD(). If you specify the password using that function and SET PASSWORD rejects the password as not being in the correct format, it may be necessary to set old_passwords to change the hashing method. See Section, “SET PASSWORD Syntax”.

You can also use a GRANT USAGE statement at the global level (ON *.*) to assign a password to an account without affecting the account's current privileges:

mysql> GRANT USAGE ON *.* TO 'jeffrey'@'localhost'
    -> IDENTIFIED BY 'mypass';

To assign a password from the command line, use the mysqladmin command:

shell> mysqladmin -u user_name -h host_name password "new_password"

The account for which this command sets the password is the one with a user table row that matches user_name in the User column and the client host from which you connect in the Host column.

During authentication when a client connects to the server, MySQL treats the password in the user table as an encrypted hash value. When assigning a password to an account, it is important to store an encrypted value, not the cleartext password. Use the following guidelines:


PASSWORD() encryption differs from Unix password encryption. See Section 6.3.1, “User Names and Passwords”.

Although it is preferable to modify passwords using SET PASSWORD, GRANT, or mysqladmin, it is also possible to modify the user table directly. In this case, you must also use FLUSH PRIVILEGES to cause the server to reread the grant tables. Otherwise, the change remains unnoticed by the server until you restart it.