GRANT
Contents
- Syntax
- Description
- Account Names
- Implicit Account Creation
- Privilege Levels
- Authentication Options
- Resource Limit Options
- TLS Options
- Roles
- Grant Examples
- See Also
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 user_specification [, user_specification] ... [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 justtbl_name
to specify a table in the default database. TheTABLE
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 justFUNCTION 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 justPROCEDURE 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_expire_logs_seconds, 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, for example via SHOW PROCESSLIST or mysqladmin processlist. If you have the PROCESS privilege, you can see all threads. Otherwise, you can see only your own threads (that is, threads associated with the MariaDB account that you are using).
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, and setting the gtid_binlog_state, gtid_domain_id, master_verify_checksum and server_id system variables. Added in MariaDB 10.5.2.
REPLICA MONITOR
Permit SHOW REPLICA STATUS and SHOW RELAYLOG EVENTS. From MariaDB 10.5.9.
When a user would upgrade from an older major release to a MariaDB 10.5 minor release prior to MariaDB 10.5.9, certain user accounts would lose capabilities. For example, a user account that had the REPLICATION CLIENT privilege in older major releases could run SHOW REPLICA STATUS, but after upgrading to a MariaDB 10.5 minor release prior to MariaDB 10.5.9, they could no longer run SHOW REPLICA STATUS, because that statement was changed to require the REPLICATION REPLICA ADMIN privilege.
This issue is fixed in MariaDB 10.5.9 with this new privilege, which now grants the user the ability to execute SHOW [ALL] (SLAVE | REPLICA) STATUS.
When a database is upgraded from an older major release to MariaDB Server 10.5.9 or later, any user accounts with the REPLICATION CLIENT or REPLICATION SLAVE privileges will automatically be granted the new REPLICA MONITOR privilege. The privilege fix occurs when the server is started up, not when mariadb-upgrade is performed.
However, when a database is upgraded from an early 10.5 minor release to 10.5.9 and later, the user will have to fix any user account privileges manually.
REPLICATION REPLICA
Synonym for REPLICATION SLAVE. From MariaDB 10.5.1.
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 REPLICA/SLAVE, STOP REPLICA/SLAVE, CHANGE MASTER, SHOW REPLICA/SLAVE STATUS, SHOW RELAYLOG EVENTS statements, replaying the binary log with the BINLOG statement (generated by mariadb-binlog), and setting the gtid_cleanup_batch_size, gtid_ignore_duplicates, gtid_pos_auto_engines, gtid_slave_pos, gtid_strict_mode, init_slave, read_binlog_speed_limit, relay_log_purge, relay_log_recovery, replicate_do_db, replicate_do_table, replicate_events_marked_for_skip, replicate_ignore_db, replicate_ignore_table, replicate_wild_do_table, replicate_wild_ignore_table, slave_compressed_protocol, slave_ddl_exec_mode, slave_domain_parallel_threads, slave_exec_mode, slave_max_allowed_packet, slave_net_timeout, slave_parallel_max_queued, slave_parallel_mode, slave_parallel_threads, slave_parallel_workers, slave_run_triggers_for_rbr, slave_sql_verify_checksum, slave_transaction_retry_interval, slave_type_conversions, sync_master_info, sync_relay_log and sync_relay_log_info system variables. Added in MariaDB 10.5.2.
SET USER
Enables setting the DEFINER
when creating triggers, views, stored functions and stored procedures. Added 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.
Privilege | Description |
---|---|
CREATE | Create 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 ROUTINE | Create Stored Programs using the CREATE PROCEDURE and CREATE FUNCTION statements. |
CREATE TEMPORARY TABLES | Create temporary tables with the CREATE TEMPORARY TABLE statement. This privilege enable writing and dropping those temporary tables |
DROP | Drop 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. |
EVENT | Create, drop and alter EVENT s. |
GRANT OPTION | Grant database privileges. You can only grant privileges that you have. |
LOCK TABLES | Acquire 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
Privilege | Description |
---|---|
ALTER | Change the structure of an existing table using the ALTER TABLE statement. |
CREATE | Create a table using the CREATE TABLE statement. You can grant the CREATE privilege on tables that do not yet exist. |
CREATE VIEW | Create a view using the CREATE_VIEW statement. |
DELETE | Remove rows from a table using the DELETE statement. |
DELETE HISTORY | Remove 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. |
DROP | Drop a table using the DROP TABLE statement or a view using the DROP VIEW statement. Also required to execute the TRUNCATE TABLE statement. |
GRANT OPTION | Grant table privileges. You can only grant privileges that you have. |
INDEX | Create 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. |
INSERT | Add rows to a table using the INSERT statement. The INSERT privilege can also be set on individual columns; see Column Privileges below for details. |
REFERENCES | Unused. |
SELECT | Read 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 VIEW | Show the CREATE VIEW statement to create a view using the SHOW CREATE VIEW statement. |
TRIGGER | Execute triggers associated to tables you update, execute the CREATE TRIGGER and DROP TRIGGER statements. You will still be able to see triggers. |
UPDATE | Update 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';
Privilege | Description |
---|---|
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
Privilege | Description |
---|---|
ALTER ROUTINE | Change the characteristics of a stored function using the ALTER FUNCTION statement. |
EXECUTE | Use a stored function. You need SELECT privileges for any tables or columns accessed by the function. |
GRANT OPTION | Grant function privileges. You can only grant privileges that you have. |
Procedure Privileges
Privilege | Description |
---|---|
ALTER ROUTINE | Change the characteristics of a stored procedure using the ALTER PROCEDURE statement. |
EXECUTE | Execute 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 OPTION | Grant procedure privileges. You can only grant privileges that you have. |
Proxy Privileges
Privilege | Description |
---|---|
PROXY | Permits 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';
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 work as alternatives ways of authenticating a user:
CREATE USER safe@'%' IDENTIFIED VIA ed25519 USING PASSWORD('secret') OR unix_socket;
By default, when you create a user without specifying an authentication plugin, MariaDB uses the mysql_native_password plugin.
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 Type | Decription |
---|---|
MAX_QUERIES_PER_HOUR | Number of statements that the account can issue per hour (including updates) |
MAX_UPDATES_PER_HOUR | Number of updates (not queries) that the account can issue per hour |
MAX_CONNECTIONS_PER_HOUR | Number of connections that the account can start per hour |
MAX_USER_CONNECTIONS | Number 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_TIME | Timeout, 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:
Option | Description |
---|---|
REQUIRE NONE | TLS is not required for this account, but can still be used. |
REQUIRE SSL | The account must use TLS, but no valid X509 certificate is required. This option cannot be combined with other TLS options. |
REQUIRE X509 | The 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/[email protected]' 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
- Troubleshooting Connection Issues
- --skip-grant-tables allows you to start MariaDB without
GRANT
. This is useful if you lost your root password. - CREATE USER
- ALTER USER
- DROP USER
- SET PASSWORD
- SHOW CREATE USER
- mysql.user table
- Password Validation Plugins - permits the setting of basic criteria for passwords
- Authentication Plugins - allow various authentication methods to be used, and new ones to be developed.