content_image/663392.jpg
-> USER AS User, -> HOST AS Host, -> CONCAT(ATTRIBUTE->>"$.fname"," ",ATTRIBUTE->>"$.lname") AS ’Full Name’, -> ATTRIBUTE->>"$.comment" AS Comment -> FROM INFORMATION_SCHEMA.USER_ATTRIBUTES -> WHERE USER=’bill’ AND HOST=’localhost’; +------+-----------+-----------------+-------------------+ | User | Host | Full Name | Comment | +------+-----------+-----------------+-------------------+ | bill | localhost | William Schmidt | Website developer | +------+-----------+-----------------+-------------------+ 1 row in set (0.00 sec) 

To set or to make changes in the user comment or user attribute for an existing user, you can use a COMMENT  or ATTRIBUTE  option with an ALTER USER  statement. 

Because the user comment and user attribute are stored together internally in a single JSON  column, this sets an upper limit on their maximum combined size; see JSON Storage Requirements, for more information. 

See also the description of the Information Schema USER_ATTRIBUTES  table for more information and examples. 

## CREATE USER Authentication Options 

An account name may be followed by an auth_option  authentication option that specifies the account authentication plugin, credentials, or both. 

<img src='content_image/663392.jpg'>

## Note 

Clauses for random password generation apply only to accounts that use an authentication plugin that stores credentials internally to MySQL. For accounts that use a plugin that performs authentication against a credentials system that is external to MySQL, password management must be handled externally against that system as well. For more information about internal credentials storage, see Section 6.2.15, “Password Management” . 

• auth_plugin  names an authentication plugin. The plugin name can be a quoted string literal or an unquoted name. Plugin names are stored in the plugin  column of the mysql.user  system table. 

For auth_option  syntax that does not specify an authentication plugin, the default plugin is indicated by the value of the default_authentication_plugin  system variable. For descriptions of each plugin, see Section 6.4.1, “Authentication Plugins” . 

•Credentials that are stored internally are stored in the mysql.user  system table. An ’ auth_string ’ value or RANDOM PASSWORD  specifies account credentials, either as a cleartext (unencrypted) string or hashed in the format expected by the authentication plugin associated with the account, respectively: 

•For syntax that uses BY ’ auth_string ’ , the string is cleartext and is passed to the authentication plugin for possible hashing. The result returned by the plugin is stored in the mysql.user  table. A plugin may use the value as specified, in which case no hashing occurs. 

•For syntax that uses BY RANDOM PASSWORD , MySQL generates a random password and as cleartext and passes it to the authentication plugin for possible hashing. The result returned by the plugin is stored in the mysql.user  table. A plugin may use the value as specified, in which case no hashing occurs. 

Randomly generated passwords are available as of MySQL 8.0.18 and have the characteristics described in Random Password Generation. 

