GRANT

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Syntax

GRANT
    priv_type [(column_list)]
      [, priv_type [(column_list)]] ...
    ON [object_type] priv_level
    TO user_specification [ user_options ...]

user_specification:
  username [authentication_option]

authentication_option:
  IDENTIFIED BY 'password' 
  | IDENTIFIED BY PASSWORD 'password_hash'
  | IDENTIFIED {VIA|WITH} authentication_rule [OR authentication_rule  ...]

authentication_rule:
    authentication_plugin
  | authentication_plugin {USING|AS} 'authentication_string'
  | authentication_plugin {USING|AS} PASSWORD('password')

GRANT PROXY ON username
    TO username [, username] ...
    [WITH GRANT OPTION]

user_options:
    [REQUIRE {NONE | tls_option [[AND] tls_option] ...}]
    [WITH with_option [with_option] ...]

object_type:
    TABLE
  | FUNCTION
  | PROCEDURE

priv_level:
    *
  | *.*
  | db_name.*
  | db_name.tbl_name
  | tbl_name
  | db_name.routine_name

with_option:
    GRANT OPTION
  | resource_option

resource_option:
  MAX_QUERIES_PER_HOUR count
  | MAX_UPDATES_PER_HOUR count
  | MAX_CONNECTIONS_PER_HOUR count
  | MAX_USER_CONNECTIONS count
  | MAX_STATEMENT_TIME time

tls_option:
  SSL 
  | X509
  | CIPHER 'cipher'
  | ISSUER 'issuer'
  | SUBJECT 'subject'

Description

The GRANT statement allows you to grant privileges or roles to accounts. To use GRANT, you must have the GRANT OPTION privilege, and you must have the privileges that you are granting.

Use the REVOKE statement to revoke privileges granted with the GRANT statement.

Use the SHOW GRANTS statement to determine what privileges an account has.

Account Names

For GRANT statements, account names are specified as the username argument in the same way as they are for CREATE USER statements. See account names from the CREATE USER page for details on how account names are specified.

Implicit Account Creation

The GRANT statement also allows you to implicitly create accounts in some cases.

If the account does not yet exist, then GRANT can implicitly create it. To implicitly create an account with GRANT, a user is required to have the same privileges that would be required to explicitly create the account with the CREATE USER statement.

If the NO_AUTO_CREATE_USER SQL_MODE is set, then accounts can only be created if authentication information is specified, or with a CREATE USER statement. If no authentication information is provided, GRANT will produce an error when the specified account does not exist, for example:

show variables like '%sql_mode%' ;
+---------------+--------------------------------------------+
| Variable_name | Value                                      |
+---------------+--------------------------------------------+
| sql_mode      | NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION |
+---------------+--------------------------------------------+

GRANT USAGE ON *.* TO 'user123'@'%' IDENTIFIED BY '';
ERROR 1133 (28000): Can't find any matching row in the user table

GRANT USAGE ON *.* TO 'user123'@'%' IDENTIFIED VIA PAM using 'mariadb' require ssl ;
Query OK, 0 rows affected (0.00 sec)
 
select host, user from mysql.user where user='user123' ;

+------+----------+
| host | user     |
+------+----------+
| %    | user123 |
+------+----------+

Privilege Levels

Privileges can be set globally, for an entire database, for a table or routine, or for individual columns in a table. Certain privileges can only be set at certain levels.

  • Global privileges priv_type are granted using *.* for priv_level. Global privileges include privileges to administer the database and manage user accounts, as well as privileges for all tables, functions, and procedures. Global privileges are stored in the mysql.user table.
  • Database privileges priv_type are granted using db_name.* for priv_level, or using just * to use default database. Database privileges include privileges to create tables and functions, as well as privileges for all tables, functions, and procedures in the database. Database privileges are stored in the mysql.db table.
  • Table privileges priv_type are granted using db_name.tbl_name for priv_level, or using just tbl_name to specify a table in the default database. The TABLE keyword is optional. Table privileges include the ability to select and change data in the table. Certain table privileges can be granted for individual columns.
  • Column privileges priv_type are granted by specifying a table for priv_level and providing a column list after the privilege type. They allow you to control exactly which columns in a table users can select and change.
  • Function privileges priv_type are granted using FUNCTION db_name.routine_name for priv_level, or using just FUNCTION routine_name to specify a function in the default database.
  • Procedure privileges priv_type are granted using PROCEDURE db_name.routine_name for priv_level, or using just PROCEDURE routine_name to specify a procedure in the default database.

The USAGE Privilege

The USAGE privilege grants no real privileges. The SHOW GRANTS statement will show a global USAGE privilege for a newly-created user. You can use USAGE with the GRANT statement to change options like GRANT OPTION and MAX_USER_CONNECTIONS without changing any account privileges.

The ALL PRIVILEGES Privilege

The ALL PRIVILEGES privilege grants all available privileges. Granting all privileges only affects the given privilege level. For example, granting all privileges on a table does not grant any privileges on the database or globally.

Using ALL PRIVILEGES does not grant the special GRANT OPTION privilege.

You can use ALL instead of ALL PRIVILEGES.

The GRANT OPTION Privilege

Use the WITH GRANT OPTION clause to give users the ability to grant privileges to other users at the given privilege level. Users with the GRANT OPTION privilege can only grant privileges they have. They cannot grant privileges at a higher privilege level than they have the GRANT OPTION privilege.

The GRANT OPTION privilege cannot be set for individual columns. If you use WITH GRANT OPTION when specifying column privileges, the GRANT OPTION privilege will be granted for the entire table.

Using the WITH GRANT OPTION clause is equivalent to listing GRANT OPTION as a privilege.

Global Privileges

The following table lists the privileges that can be granted globally. You can also grant all database, table, and function privileges globally. When granted globally, these privileges apply to all databases, tables, or functions, including those created later.

To set a global privilege, use *.* for priv_level.

BINLOG ADMIN

Enables administration of the binary log, including the PURGE BINARY LOGS statement and setting the binlog_annotate_row_events, binlog_cache_size, binlog_commit_wait_count, binlog_commit_wait_usec, binlog_direct_non_transactional_updates, binlog_file_cache_size, binlog_format, binlog_row_image, binlog_row_metadata, binlog_stmt_cache_size, expire_logs_days, log_bin_compress, log_bin_compress_min_len, log_bin_trust_function_creators, max_binlog_cache_size, max_binlog_size, max_binlog_stmt_cache_size, sql_log_bin and sync_binlog system variables. Added in MariaDB 10.5.2.

BINLOG MONITOR

New name for REPLICATION CLIENT from MariaDB 10.5.2, (REPLICATION CLIENT still supported as an alias for compatibility purposes). Permits running SHOW commands related to the binary log, in particular the SHOW BINLOG STATUS, SHOW REPLICA STATUS and SHOW BINARY LOGS statements.

BINLOG REPLAY

Enables replaying the binary log with the BINLOG statement (generated by mariadb-binlog), executing SET timestamp when secure_timestamp is set to replication, and setting the session values of system variables usually included in BINLOG output, in particular gtid_domain_id, gtid_seq_no, pseudo_thread_id and server_id. Added in MariaDB 10.5.2

CONNECTION ADMIN

Enables administering connection resource limit options. This includes ignoring the limits specified by max_connections, max_user_connections and max_password_errors, not executing the statements specified in init_connect, killing connections and queries owned by other users as well as setting the following connection-related system variables: connect_timeout, disconnect_on_expired_password, extra_max_connections, init_connect, max_connections, max_connect_errors, max_password_errors, proxy_protocol_networks, secure_auth, slow_launch_time, thread_pool_exact_stats, thread_pool_dedicated_listener, thread_pool_idle_timeout, thread_pool_max_threads, thread_pool_min_threads, thread_pool_mode, thread_pool_oversubscribe, thread_pool_prio_kickup_timer, thread_pool_priority, thread_pool_size, thread_pool_stall_limit. Added in MariaDB 10.5.2.

CREATE USER

Create a user using the CREATE USER statement, or implicitly create a user with the GRANT statement.

FEDERATED ADMIN

Execute CREATE SERVER, ALTER SERVER, and DROP SERVER statements. Added in MariaDB 10.5.2.

FILE

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 the permissions to access those files.

GRANT OPTION

Grant global privileges. You can only grant privileges that you have.

PROCESS

Show information about the active processes, via SHOW PROCESSLIST or mysqladmin processlist.

READ_ONLY ADMIN

User can set the read_only system variable and allows the user to perform write operations, even when the read_only option is active. Added in MariaDB 10.5.2.

RELOAD

Execute FLUSH statements or equivalent mariadb-admin/mysqladmin commands.

REPLICATION CLIENT

Execute SHOW MASTER STATUS, SHOW SLAVE STATUS and SHOW BINARY LOGS informative statements. Renamed to BINLOG MONITOR in MariaDB 10.5.2 (but still supported as an alias for compatibility reasons).

REPLICATION MASTER ADMIN

Permits administration of primary servers, including the SHOW REPLICA HOSTS statement. Added in MariaDB 10.5.2.

REPLICATION SLAVE

Accounts used by replica servers on the primary need this privilege. This is needed to get the updates made on the master. From MariaDB 10.5.1, REPLICATION REPLICA is an alias for REPLICATION SLAVE.

REPLICATION SLAVE ADMIN

Permits administering replica servers, including START SLAVE, STOP SLAVE, CHANGE MASTER, SHOW SLAVE STATUS, SHOW RELAYLOG EVENTS statements (new in MariaDB 10.5.2).

SET USER

Enables setting the DEFINER when creating triggers, views, stored functions and stored procedures (new in MariaDB 10.5.2).

SHOW DATABASES

List all databases using the SHOW DATABASES statement. Without the SHOW DATABASES privilege, you can still issue the SHOW DATABASES statement, but it will only list databases containing tables on which you have privileges.

SHUTDOWN

Shut down the server using SHUTDOWN or the mysqladmin shutdown command.

SUPER

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 mysqladmin 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 replica, 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.

The SUPER privilege has been split into multiple smaller privileges from MariaDB 10.5.2 to allow for more fine-grained privileges, although it remains an alias for these smaller privileges.

Database Privileges

The following table lists the privileges that can be granted at the database level. You can also grant all table and function privileges at the database level. Table and function privileges on a database apply to all tables or functions in that database, including those created later.

To set a privilege for a database, specify the database using db_name.* for priv_level, or just use * to specify the default database.

PrivilegeDescription
CREATECreate a database using the CREATE DATABASE statement, when the privilege is granted for a database. You can grant the CREATE privilege on databases that do not yet exist. This also grants the CREATE privilege on all tables in the database.
CREATE ROUTINECreate Stored Programs using the CREATE PROCEDURE and CREATE FUNCTION statements.
CREATE TEMPORARY TABLESCreate temporary tables with the CREATE TEMPORARY TABLE statement. This privilege enable writing and dropping those temporary tables
DROPDrop a database using the DROP DATABASE statement, when the privilege is granted for a database. This also grants the DROP privilege on all tables in the database.
EVENTCreate, drop and alter EVENTs. Added in MySQL 5.1.6.
GRANT OPTIONGrant database privileges. You can only grant privileges that you have.
LOCK TABLESAcquire explicit locks using the LOCK TABLES statement; you also need to have the SELECT privilege on a table, in order to lock it.

Table Privileges

PrivilegeDescription
ALTERChange the structure of an existing table using the ALTER TABLE statement.
CREATECreate a table using the CREATE TABLE statement. You can grant the CREATE privilege on tables that do not yet exist.
CREATE VIEWCreate a view using the CREATE_VIEW statement.
DELETERemove rows from a table using the DELETE statement.
DELETE HISTORYRemove historical rows from a table using the DELETE HISTORY statement. Displays as DELETE VERSIONING ROWS when running SHOW GRANTS until MariaDB 10.3.15 and until MariaDB 10.4.5 (MDEV-17655), or when running SHOW PRIVILEGES until MariaDB 10.5.2, MariaDB 10.4.13 and MariaDB 10.3.23 (MDEV-20382). From MariaDB 10.3.4. From MariaDB 10.3.5, if a user has the SUPER privilege but not this privilege, running mysql_upgrade will grant this privilege as well.
DROPDrop a table using the DROP TABLE statement or a view using the DROP VIEW statement. Also required to execute the TRUNCATE TABLE statement.
GRANT OPTIONGrant table privileges. You can only grant privileges that you have.
INDEXCreate an index on a table using the CREATE INDEX statement. Without the INDEX privilege, you can still create indexes when creating a table using the CREATE TABLE statement if the you have the CREATE privilege, and you can create indexes using the ALTER TABLE statement if you have the ALTER privilege.
INSERTAdd rows to a table using the INSERT statement. The INSERT privilege can also be set on individual columns; see Column Privileges below for details.
REFERENCESUnused.
SELECTRead data from a table using the SELECT statement. The SELECT privilege can also be set on individual columns; see Column Privileges below for details.
SHOW VIEWShow the CREATE VIEW statement to create a view using the SHOW CREATE VIEW statement.
TRIGGERExecute triggers associated to tables you update, execute the CREATE TRIGGER and DROP TRIGGER statements. You will still be able to see triggers.
UPDATEUpdate existing rows in a table using the UPDATE statement. UPDATE statements usually include a WHERE clause to update only certain rows. You must have SELECT privileges on the table or the appropriate columns for the WHERE clause. The UPDATE privilege can also be set on individual columns; see Column Privileges below for details.

Column Privileges

Some table privileges can be set for individual columns of a table. To use column privileges, specify the table explicitly and provide a list of column names after the privilege type. For example, the following statement would allow the user to read the names and positions of employees, but not other information from the same table, such as salaries.

GRANT SELECT (name, position) on Employee to 'jeffrey'@'localhost';
PrivilegeDescription
INSERT (column_list)Add rows specifying values in columns using the INSERT statement. If you only have column-level INSERT privileges, you must specify the columns you are setting in the INSERT statement. All other columns will be set to their default values, or NULL.
REFERENCES (column_list)Unused.
SELECT (column_list)Read values in columns using the SELECT statement. You cannot access or query any columns for which you do not have SELECT privileges, including in WHERE, ON, GROUP BY, and ORDER BY clauses.
UPDATE (column_list)Update values in columns of existing rows using the UPDATE statement. UPDATE statements usually include a WHERE clause to update only certain rows. You must have SELECT privileges on the table or the appropriate columns for the WHERE clause.

Function Privileges

PrivilegeDescription
ALTER ROUTINEChange the characteristics of a stored function using the ALTER FUNCTION statement.
EXECUTEUse a stored function. You need SELECT privileges for any tables or columns accessed by the function.
GRANT OPTIONGrant function privileges. You can only grant privileges that you have.

Procedure Privileges

PrivilegeDescription
ALTER ROUTINEChange the characteristics of a stored procedure using the ALTER PROCEDURE statement.
EXECUTEExecute a stored procedure using the CALL statement. The privilege to call a procedure may allow you to perform actions you wouldn't otherwise be able to do, such as insert rows into a table.
GRANT OPTIONGrant procedure privileges. You can only grant privileges that you have.

Proxy Privileges

PrivilegeDescription
PROXYPermits one user to be a proxy for another.

The PROXY privilege allows one user to proxy as another user, which means their privileges change to that of the proxy user, and the CURRENT_USER() function returns the user name of the proxy user.

The PROXY privilege only works with authentication plugins that support it. The default mysql_native_password authentication plugin does not support proxy users.

The pam authentication plugin is the only plugin included with MariaDB that currently supports proxy users. The PROXY privilege is commonly used with the pam authentication plugin to enable user and group mapping with PAM.

For example, to grant the PROXY privilege to an anonymous account that authenticates with the pam authentication plugin, you could execute the following:

CREATE USER 'dba'@'%' IDENTIFIED BY 'strongpassword';
GRANT ALL PRIVILEGES ON *.* TO 'dba'@'%' ;

CREATE USER ''@'%' IDENTIFIED VIA pam USING 'mariadb';
GRANT PROXY ON 'dba'@'%' TO ''@'%';

A user account can only grant the PROXY privilege for a specific user account if the granter also has the PROXY privilege for that specific user account, and if that privilege is defined WITH GRANT OPTION. For example, the following example fails because the granter does not have the PROXY privilege for that specific user account at all:

SELECT USER(), CURRENT_USER();
+-----------------+-----------------+
| USER()          | CURRENT_USER()  |
+-----------------+-----------------+
| alice@localhost | alice@localhost |
+-----------------+-----------------+

SHOW GRANTS;
+-----------------------------------------------------------------------------------------------------------------------+
| Grants for alice@localhost                                                                                            |
+-----------------------------------------------------------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'alice'@'localhost' IDENTIFIED BY PASSWORD '*2470C0C06DEE42FD1618BB99005ADCA2EC9D1E19' |
+-----------------------------------------------------------------------------------------------------------------------+

GRANT PROXY ON 'dba'@'localhost' TO 'bob'@'localhost';
ERROR 1698 (28000): Access denied for user 'alice'@'localhost'

And the following example fails because the granter does have the PROXY privilege for that specific user account, but it is not defined WITH GRANT OPTION:

SELECT USER(), CURRENT_USER();
+-----------------+-----------------+
| USER()          | CURRENT_USER()  |
+-----------------+-----------------+
| alice@localhost | alice@localhost |
+-----------------+-----------------+

SHOW GRANTS;
+-----------------------------------------------------------------------------------------------------------------------+
| Grants for alice@localhost                                                                                            |
+-----------------------------------------------------------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'alice'@'localhost' IDENTIFIED BY PASSWORD '*2470C0C06DEE42FD1618BB99005ADCA2EC9D1E19' |
| GRANT PROXY ON 'dba'@'localhost' TO 'alice'@'localhost'                                                               |
+-----------------------------------------------------------------------------------------------------------------------+

GRANT PROXY ON 'dba'@'localhost' TO 'bob'@'localhost';
ERROR 1698 (28000): Access denied for user 'alice'@'localhost'

But the following example succeeds because the granter does have the PROXY privilege for that specific user account, and it is defined WITH GRANT OPTION:

SELECT USER(), CURRENT_USER();
+-----------------+-----------------+
| USER()          | CURRENT_USER()  |
+-----------------+-----------------+
| alice@localhost | alice@localhost |
+-----------------+-----------------+

SHOW GRANTS;
+-----------------------------------------------------------------------------------------------------------------------------------------+
| Grants for alice@localhost                                                                                                              |
+-----------------------------------------------------------------------------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'alice'@'localhost' IDENTIFIED BY PASSWORD '*2470C0C06DEE42FD1618BB99005ADCA2EC9D1E19' WITH GRANT OPTION |
| GRANT PROXY ON 'dba'@'localhost' TO 'alice'@'localhost' WITH GRANT OPTION                                                               |
+-----------------------------------------------------------------------------------------------------------------------------------------+

GRANT PROXY ON 'dba'@'localhost' TO 'bob'@'localhost';
Query OK, 0 rows affected (0.004 sec)

A user account can grant the PROXY privilege for any other user account if the granter has the PROXY privilege for the ''@'%' anonymous user account, like this:

GRANT PROXY ON ''@'%' TO 'dba'@'localhost' WITH GRANT OPTION;

For example, the following example succeeds because the user can grant the PROXY privilege for any other user account:

SELECT USER(), CURRENT_USER();
+-----------------+-----------------+
| USER()          | CURRENT_USER()  |
+-----------------+-----------------+
| alice@localhost | alice@localhost |
+-----------------+-----------------+

SHOW GRANTS;
+-----------------------------------------------------------------------------------------------------------------------------------------+
| Grants for alice@localhost                                                                                                              |
+-----------------------------------------------------------------------------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'alice'@'localhost' IDENTIFIED BY PASSWORD '*2470C0C06DEE42FD1618BB99005ADCA2EC9D1E19' WITH GRANT OPTION |
| GRANT PROXY ON ''@'%' TO 'alice'@'localhost' WITH GRANT OPTION                                                                          |
+-----------------------------------------------------------------------------------------------------------------------------------------+

GRANT PROXY ON 'app1_dba'@'localhost' TO 'bob'@'localhost';
Query OK, 0 rows affected (0.004 sec)

GRANT PROXY ON 'app2_dba'@'localhost' TO 'carol'@'localhost';
Query OK, 0 rows affected (0.004 sec)

The default root user accounts created by mysql_install_db have this privilege. For example:

GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION;
GRANT PROXY ON ''@'%' TO 'root'@'localhost' WITH GRANT OPTION;

This allows the default root user accounts to grant the PROXY privilege for any other user account, and it also allows the default root user accounts to grant others the privilege to do the same.

Authentication Options

The authentication options for the GRANT statement are the same as those for the CREATE USER statement.

IDENTIFIED BY 'password'

The optional IDENTIFIED BY clause can be used to provide an account with a password. The password should be specified in plain text. It will be hashed by the PASSWORD function prior to being stored to the mysql.user table.

For example, if our password is mariadb, then we can create the user with:

GRANT USAGE ON *.* TO foo2@test IDENTIFIED BY 'mariadb';

If you do not specify a password with the IDENTIFIED BY clause, the user will be able to connect without a password. A blank password is not a wildcard to match any password. The user must connect without providing a password if no password is set.

If the user account already exists and if you provide the IDENTIFIED BY clause, then the user's password will be changed. You must have the privileges needed for the SET PASSWORD statement to change a user's password with GRANT.

The only authentication plugins that this clause supports are mysql_native_password and mysql_old_password.

IDENTIFIED BY PASSWORD 'password_hash'

The optional IDENTIFIED BY PASSWORD clause can be used to provide an account with a password that has already been hashed. The password should be specified as a hash that was provided by the PASSWORD function. It will be stored to the mysql.user table as-is.

For example, if our password is mariadb, then we can find the hash with:

SELECT PASSWORD('mariadb');
+-------------------------------------------+
| PASSWORD('mariadb')                       |
+-------------------------------------------+
| *54958E764CE10E50764C2EECBB71D01F08549980 |
+-------------------------------------------+
1 row in set (0.00 sec)

And then we can create a user with the hash:

GRANT USAGE ON *.* TO foo2@test IDENTIFIED BY PASSWORD '*54958E764CE10E50764C2EECBB71D01F08549980';

If you do not specify a password with the IDENTIFIED BY clause, the user will be able to connect without a password. A blank password is not a wildcard to match any password. The user must connect without providing a password if no password is set.

If the user account already exists and if you provide the IDENTIFIED BY clause, then the user's password will be changed. You must have the privileges needed for the SET PASSWORD statement to change a user's password with GRANT.

The only authentication plugins that this clause supports are mysql_native_password and mysql_old_password.

IDENTIFIED {VIA|WITH} authentication_plugin

The optional IDENTIFIED VIA authentication_plugin allows you to specify that the account should be authenticated by a specific authentication plugin. The plugin name must be an active authentication plugin as per SHOW PLUGINS. If it doesn't show up in that output, then you will need to install it with INSTALL PLUGIN or INSTALL SONAME.

For example, this could be used with the PAM authentication plugin:

GRANT USAGE ON *.* TO foo2@test IDENTIFIED VIA pam;

Some authentication plugins allow additional arguments to be specified after a USING or AS keyword. For example, the PAM authentication plugin accepts a service name:

GRANT USAGE ON *.* TO foo2@test IDENTIFIED VIA pam USING 'mariadb';

The exact meaning of the additional argument would depend on the specific authentication plugin.

MariaDB starting with 10.4.0

The USING or AS keyword can also be used to provide a plain-text password to a plugin if it's provided as an argument to the PASSWORD() function. This is only valid for authentication plugins that have implemented a hook for the PASSWORD() function. For example, the ed25519 authentication plugin supports this:

CREATE USER safe@'%' IDENTIFIED VIA ed25519 USING PASSWORD('secret');
MariaDB starting with 10.4.3

One can specify many authentication plugins, they all works as alternatives ways of authenticating a user:

CREATE USER safe@'%' IDENTIFIED VIA ed25519 USING PASSWORD('secret') OR unix_socket;

Resource Limit Options

MariaDB starting with 10.2.0

MariaDB 10.2.0 introduced a number of resource limit options.

It is possible to set per-account limits for certain server resources. The following table shows the values that can be set per account:

Limit TypeDecription
MAX_QUERIES_PER_HOURNumber of statements that the account can issue per hour (including updates)
MAX_UPDATES_PER_HOURNumber of updates (not queries) that the account can issue per hour
MAX_CONNECTIONS_PER_HOURNumber of connections that the account can start per hour
MAX_USER_CONNECTIONSNumber of simultaneous connections that can be accepted from the same account; if it is 0, max_connections will be used instead; if max_connections is 0, there is no limit for this account's simultaneous connections.
MAX_STATEMENT_TIMETimeout, in seconds, for statements executed by the user. See also Aborting Statements that Exceed a Certain Time to Execute.

If any of these limits are set to 0, then there is no limit for that resource for that user.

To set resource limits for an account, if you do not want to change that account's privileges, you can issue a GRANT statement with the USAGE privilege, which has no meaning. The statement can name some or all limit types, in any order.

Here is an example showing how to set resource limits:

GRANT USAGE ON *.* TO 'someone'@'localhost' WITH
    MAX_USER_CONNECTIONS 0
    MAX_QUERIES_PER_HOUR 200;

The resources are tracked per account, which means 'user'@'server'; not per user name or per connection.

The count can be reset for all users using FLUSH USER_RESOURCES, FLUSH PRIVILEGES or mysqladmin reload.

Users with the CONNECTION ADMIN privilege (in MariaDB 10.5.2 and later) or the SUPER privilege are not restricted by max_user_connections, max_connections, or max_password_errors.

Per account resource limits are stored in the user table, in the mysql database. Columns used for resources limits are named max_questions, max_updates, max_connections (for MAX_CONNECTIONS_PER_HOUR), and max_user_connections (for MAX_USER_CONNECTIONS).

TLS Options

By default, MariaDB transmits data between the server and clients without encrypting it. This is generally acceptable when the server and client run on the same host or in networks where security is guaranteed through other means. However, in cases where the server and client exist on separate networks or they are in a high-risk network, the lack of encryption does introduce security concerns as a malicious actor could potentially eavesdrop on the traffic as it is sent over the network between them.

To mitigate this concern, MariaDB allows you to encrypt data in transit between the server and clients using the Transport Layer Security (TLS) protocol. TLS was formerly known as Secure Socket Layer (SSL), but strictly speaking the SSL protocol is a predecessor to TLS and, that version of the protocol is now considered insecure. The documentation still uses the term SSL often and for compatibility reasons TLS-related server system and status variables still use the prefix ssl_, but internally, MariaDB only supports its secure successors.

See Secure Connections Overview for more information about how to determine whether your MariaDB server has TLS support.

You can set certain TLS-related restrictions for specific user accounts. For instance, you might use this with user accounts that require access to sensitive data while sending it across networks that you do not control. These restrictions can be enabled for a user account with the CREATE USER, ALTER USER, or GRANT statements. The following options are available:

OptionDescription
REQUIRE NONETLS is not required for this account, but can still be used.
REQUIRE SSLThe account must use TLS, but no valid X509 certificate is required. This option cannot be combined with other TLS options.
REQUIRE X509The account must use TLS and must have a valid X509 certificate. This option implies REQUIRE SSL. This option cannot be combined with other TLS options.
REQUIRE ISSUER 'issuer'The account must use TLS and must have a valid X509 certificate. Also, the Certificate Authority must be the one specified via the string issuer. This option implies REQUIRE X509. This option can be combined with the SUBJECT, and CIPHER options in any order.
REQUIRE SUBJECT 'subject'The account must use TLS and must have a valid X509 certificate. Also, the certificate's Subject must be the one specified via the string subject. This option implies REQUIRE X509. This option can be combined with the ISSUER, and CIPHER options in any order.
REQUIRE CIPHER 'cipher'The account must use TLS, but no valid X509 certificate is required. Also, the encryption used for the connection must use one of the methods specified in the string cipher. This option implies REQUIRE SSL. This option can be combined with the ISSUER, and SUBJECT options in any order.

The REQUIRE keyword must be used only once for all specified options, and the AND keyword can be used to separate individual options, but it is not required.

For example, you can create a user account that requires these TLS options with the following:

GRANT USAGE ON *.* TO 'alice'@'%'
    REQUIRE SUBJECT '/CN=alice/O=My Dom, Inc./C=US/ST=Oregon/L=Portland'
    AND ISSUER '/C=FI/ST=Somewhere/L=City/ O=Some Company/CN=Peter Parker/emailAddress=p.parker@marvel.com'
    AND CIPHER 'TLSv1.2';

If any of these options are set for a specific user account, then any client who tries to connect with that user account will have to be configured to connect with TLS.

See Securing Connections for Client and Server for information on how to enable TLS on the client and server.

Roles

Syntax

GRANT role TO grantee [, grantee2 ... ]
[ WITH ADMIN OPTION ]

The GRANT statement is also used to grant the use a role to one or more users or other roles. In order to be able to grant a role, the grantor doing so must have permission to do so (see WITH ADMIN in the CREATE ROLE article).

Specifying the WITH ADMIN OPTION permits the grantee to in turn grant the role to another.

For example, the following commands show how to grant the same role to a couple different users.

GRANT journalist TO hulda;

GRANT journalist TO berengar WITH ADMIN OPTION;

If a user has been granted a role, they do not automatically obtain all permissions associated with that role. These permissions are only in use when the user activates the role with the SET ROLE statement.

Grant Examples

Granting Root-like Privileges

You can create a user that has privileges similar to the default root accounts by executing the following:

CREATE USER 'alexander'@'localhost';
GRANT ALL PRIVILEGES ON  *.* to 'alexander'@'localhost' WITH GRANT OPTION;

See Also

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