mysql.user Table
System tables should not normally be edited directly. Use the related SQL statements instead.
The mysql.global_priv table has replaced the mysql.user table, and mysql.user should be considered obsolete. It is now a view into mysql.global_priv created for compatibility with older applications and monitoring scripts. New tools are supposed to use INFORMATION_SCHEMA tables. The dedicated mariadb.sys user is created as the definer of the view. Previously, root was the definer, which resulted in privilege problems when this username was changed (MDEV-19650).
The mysql.user table contains information about users that have permission to access the MariaDB server, and their global privileges. The table can be queried and although it is possible to directly update it, it is best to use GRANT and CREATE USER for adding users and privileges.
Note that the MariaDB privileges occur at many levels. A user may not be granted create privilege at the user level, but may still have create permission on certain tables or databases, for example. See privileges for a more complete view of the MariaDB privilege system.
The mysql.user table contains the following fields:
Field
Type
Null
Key
Default
Description
Host
char(60)
NO
PRI
Host (together with User makes up the unique identifier for this account.
User
char(80)
NO
PRI
User (together with Host makes up the unique identifier for this account.
Process_priv
enum('N','Y')
NO
N
Can show information about active processes, via SHOW PROCESSLIST or mariadb-admin processlist.
File_priv
enum('N','Y')
NO
N
Read and write files on the server, using statements like LOAD DATA INFILE or functions like LOAD_FILE(). Also needed to create CONNECT outward tables. MariaDB server must have permission to access those files.
References_priv
enum('N','Y')
NO
N
Unused
Index_priv
enum('N','Y')
NO
N
Can create an index on a table using the CREATE INDEX statement. Without the INDEX privilege, user can still create indexes when creating a table using the CREATE TABLE statement if the user has have the CREATE privilege, and user can create indexes using the ALTER TABLE statement if they have the ALTER privilege.
Show_db_priv
enum('N','Y')
NO
N
Can list all databases using the SHOW DATABASES statement. Without the SHOW DATABASES privilege, user can still issue the SHOW DATABASES statement, but it will only list databases containing tables on which they have privileges.
Super_priv
enum('N','Y')
NO
N
Can execute superuser statements: CHANGE MASTER TO, KILL (users who do not have this privilege can only KILL their own threads), PURGE LOGS, SET global system variables, or the mariadb-admin debug command. Also, this permission allows the user to write data even if the read_only startup option is set, enable or disable logging, enable or disable replication on slaves, specify a DEFINER for statements that support that clause, connect once after reaching the MAX_CONNECTIONS. If a statement has been specified for the init-connect mysqld option, that command will not be executed when a user with SUPER privileges connects to the server.
Create_tmp_table_priv
enum('N','Y')
NO
N
Can create temporary tables with the CREATE TEMPORARY TABLE statement.
Lock_tables_priv
enum('N','Y')
NO
N
Acquire explicit locks using the LOCK TABLES statement; user also needs to have the SELECT privilege on a table in order to lock it.
Repl_slave_priv
enum('N','Y')
NO
N
Accounts used by slave servers on the master need this privilege. This is needed to get the updates made on the master.
Show_view_priv
enum('N','Y')
NO
N
Can show the CREATE VIEW statement to create a view using the SHOW CREATE VIEW statement.
Create_routine_priv
enum('N','Y')
NO
N
Can create stored programs using the CREATE PROCEDURE and CREATE FUNCTION statements.
Alter_routine_priv
enum('N','Y')
NO
N
Can change the characteristics of a stored function using the ALTER FUNCTION statement.
Create_user_priv
enum('N','Y')
NO
N
Can create a user using the CREATE USER statement, or implicitly create a user with the GRANT statement.
Trigger_priv
enum('N','Y')
NO
N
Can execute triggers associated with tables the user updates, execute the CREATE TRIGGER and DROP TRIGGER statements.
Create_tablespace_priv
enum('N','Y')
NO
N
max_questions
int(11) unsigned
NO
0
Number of queries the user can perform per hour. Zero is unlimited. See per-account resource limits.
max_updates
int(11) unsigned
NO
0
Number of updates the user can perform per hour. Zero is unlimited. See per-account resource limits.
max_connections
int(11) unsigned
NO
0
Number of connections the account can start per hour. Zero is unlimited. See per-account resource limits.
max_user_connections
int(11)
NO
0
Number of simultaneous connections the account can have. Zero is unlimited. See per-account resource limits.
authentication_string
text
NO
NULL
Authentication string for the authentication plugin.
password_expired
enum('N','Y')
NO
N
MySQL-compatibility option, not implemented in MariaDB.
default_role
char(80)
NO
N
Role which will be enabled on user login automatically.
max_statement_time
decimal(12,6)
NO
0.000000
If non-zero, how long queries can run before being killed automatically.
Field
Type
Null
Key
Default
Description
The Acl_roles status variable indicates how many rows the mysql.user table contains where is_role='Y'.
The Acl_users status variable, indicates how many rows the mysql.user table contains where is_role='N'.
Authentication Plugin
When the plugin column is empty, MariaDB defaults to authenticating accounts with either the mysql_native_password or the mysql_old_password plugins. It decides which based on the hash used in the value for the Password column. When there's no password set or when the 4.1 password hash is used, (which is 41 characters long), MariaDB uses the mysql_native_password plugin. The mysql_old_password plugin is used with pre-4.1 password hashes, (which are 16 characters long).
MariaDB also supports the use of alternative authentication plugins. When the plugin column is not empty for the given account, MariaDB uses it to authenticate connection attempts. The specific plugin then uses the value of either the Password column or the authentication_string column to authenticate the user.
A specific authentication plugin can be used for an account by providing the IDENTIFIED VIA authentication_plugin clause with the CREATE USER, ALTER USER, or GRANT statements.
For example, the following statement would create an account that authenticates with the PAM authentication plugin:
CREATE USER foo2@test IDENTIFIED VIA pam;If the specific authentication plugin uses the authentication_string column, then this value for the account can be specified after a USING or AS keyword. For example, the PAM authentication plugin accepts a service name that would go into the authentication_string column for the account:
CREATE USER foo2@test IDENTIFIED VIA pam USING 'mariadb';This page is licensed: CC BY-SA / Gnu FDL
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