CREATE USER

Syntax

CREATE [OR REPLACE] USER [IF NOT EXISTS] 
 user_specification [,user_specification] ...
  [REQUIRE {NONE | tls_option [[AND] tls_option] ...}]
  [WITH resource_option [resource_option] ...]
  [password_option] 

user_specification:
  username [authentication_option]

authentication_option:
  IDENTIFIED BY 'password' 
  | IDENTIFIED BY PASSWORD 'password_hash'
  | IDENTIFIED {VIA|WITH} authentication_plugin
  | IDENTIFIED {VIA|WITH} authentication_plugin {USING|AS} 'authentication_string'
  | IDENTIFIED {VIA|WITH} authentication_plugin {USING|AS} PASSWORD('password')

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

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

password_option:
  PASSWORD EXPIRE
  | PASSWORD EXPIRE DEFAULT
  | PASSWORD EXPIRE NEVER
  | PASSWORD EXPIRE INTERVAL N DAY

Description

The CREATE USER statement creates new MariaDB accounts. To use it, you must have the global CREATE USER privilege or the INSERT privilege for the mysql database. For each account, CREATE USER creates a new row in the mysql.user table that has no privileges.

If any of the specified accounts, or any permissions for the specified accounts, already exist, then the server returns ERROR 1396 (HY000). If an error occurs, CREATE USER will still create the accounts that do not result in an error. Only one error is produced for all users which have not been created:

ERROR 1396 (HY000): 
  Operation CREATE USER failed for 'u1'@'%','u2'@'%'

CREATE USER, DROP USER, CREATE ROLE, and DROP ROLE all produce the same error code when they fail.

See Account Names below for details on how account names are specified.

OR REPLACE

MariaDB starting with 10.1.3

If the optional OR REPLACE clause is used, it is basically a shortcut for:

DROP USER IF EXISTS name;
CREATE USER name ...;

For example:

CREATE USER foo2@test IDENTIFIED BY 'password';
ERROR 1396 (HY000): Operation CREATE USER failed for 'foo2'@'test'

CREATE OR REPLACE USER foo2@test IDENTIFIED BY 'password';
Query OK, 0 rows affected (0.00 sec)

IF NOT EXISTS

MariaDB starting with 10.1.3

When the IF NOT EXISTS clause is used, MariaDB will return a warning instead of an error if the specified user already exists.

For example:

CREATE USER foo2@test IDENTIFIED BY 'password';
ERROR 1396 (HY000): Operation CREATE USER failed for 'foo2'@'test'

CREATE USER IF NOT EXISTS foo2@test IDENTIFIED BY 'password';
Query OK, 0 rows affected, 1 warning (0.00 sec)

SHOW WARNINGS;
+-------+------+----------------------------------------------------+
| Level | Code | Message                                            |
+-------+------+----------------------------------------------------+
| Note  | 1973 | Can't create user 'foo2'@'test'; it already exists |
+-------+------+----------------------------------------------------+
1 row in set (0.00 sec

Authentication Options

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:

CREATE USER 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.

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:

CREATE USER 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.

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:

CREATE USER 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:

CREATE USER foo2@test IDENTIFIED VIA pam USING 'mariadb';

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

In MariaDB 10.4 and later, 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');

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.
REQUIRE X509The account must use TLS and must have a valid X509 certificate.
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.
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.
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.

If you set REQUIRE X509, then REQUIRE SSL is implicitly set. If you set ISSUER and/or SUBJECT, then REQUIRE X509 is also implicitly set. The ISSUER, SUBJECT, and CIPHER options can be set together 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:

CREATE USER '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.

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.

Here is an example showing how to create a user with resource limits:

CREATE USER 'someone'@'localhost' WITH
    MAX_USER_CONNECTIONS 10
    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.

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).

Account Names

Account names have both a user name component and a host name component, and are specified as 'user_name'@'host_name'.

The user name and host name may be unquoted, quoted as strings using double quotes (") or single quotes ('), or quoted as identifiers using backticks (`). You must use quotes when using special characters (such as a hyphen) or wildcard characters. If you quote, you must quote the user name and host name separately (for example 'user_name'@'host_name').

Host Name Component

If the host name is not provided, it is assumed to be '%'.

Host names may contain the wildcard characters % and _. They are matched as if by the LIKE clause. If you need to use a wildcard character literally (for example, to match a domain name with an underscore), prefix the character with a backslash. See LIKE for more information on escaping wildcard characters.

Host name matches are case-insensitive. Host names can match either domain names or IP addresses. Use 'localhost' as the host name to allow only local client connections.

You can use a netmask to match a range of IP addresses using 'base_ip/netmask' as the host name. A user with an IP address ip_addr will be allowed to connect if the following condition is true:

ip_addr & netmask = base_ip

You can only use netmasks that specify a multiple of 8 bits of the address to match. That is, only the following netmasks are allowed:

255.0.0.0
255.255.0.0
255.255.255.0
255.255.255.255

Using 255.255.255.255 is equivalent to not using a netmask at all.

User Name Component

User names must match exactly, including case. A user name that is empty is name as as an anonymous account and is allowed to match a login attempt with any user name component. These are described more in the next section.

For valid identifiers to use as user names, see Identifier Names.

It is possible for more than one account to match when a user connects. MariaDB selects the first matching account after sorting according to the following criteria:

  • Accounts with an exact host name are sorted before accounts using a wildcard in the host name. Host names using a netmask are considered to be exact for sorting.
  • Accounts with a wildcard in the host name are sorted according to the position of the first wildcard character. Those with a wildcard character later in the host name sort before those with a wildcard character earlier in the host name.
  • Accounts with a non-empty user name sort before accounts with an empty user name.
  • Accounts with an empty user name are sorted last. As mentioned previously, these are known as anonymous accounts. These are described more in the next section.

The following table shows a list of example account as sorted by these criteria:

+---------+-------------+
| User    | Host        |
+---------+-------------+
| joffrey | 192.168.0.3 |
|         | 192.168.0.% |
| joffrey | 192.168.%   |
|         | 192.168.%   |
+---------+-------------+

Once connected, you only have the privileges granted to the account that matched, not all accounts that could have matched. For example, consider the following commands:

CREATE USER 'joffrey'@'192.168.0.3';
CREATE USER 'joffrey'@'%';
GRANT SELECT ON test.t1 to 'joffrey'@'192.168.0.3';
GRANT SELECT ON test.t2 to 'joffrey'@'%';

If you connect as joffrey from 192.168.0.3, you will have the SELECT privilege on the table test.t1, but not on the table test.t2. If you connect as joffrey from any other IP address, you will have the SELECT privilege on the table test.t2, but not on the table test.t1.

MariaDB starting with 5.5.31

Beginning with MariaDB 5.5.31, usernames can be up to 80 characters long. From MariaDB 10.0 the system tables are all by default this length. However, in order to enable this feature in MariaDB 5.5, the following schema changes must be made:

ALTER TABLE mysql.user         MODIFY User         CHAR(80)  BINARY NOT NULL DEFAULT '';
ALTER TABLE mysql.db           MODIFY User         CHAR(80)  BINARY NOT NULL DEFAULT '';
ALTER TABLE mysql.tables_priv  MODIFY User         CHAR(80)  BINARY NOT NULL DEFAULT '';
ALTER TABLE mysql.columns_priv MODIFY User         CHAR(80)  BINARY NOT NULL DEFAULT '';
ALTER TABLE mysql.procs_priv   MODIFY User         CHAR(80)  BINARY NOT NULL DEFAULT '';
ALTER TABLE mysql.proc         MODIFY definer      CHAR(141) COLLATE utf8_bin NOT NULL DEFAULT '';
ALTER TABLE mysql.event        MODIFY definer      CHAR(141) COLLATE utf8_bin NOT NULL DEFAULT '';
ALTER TABLE mysql.proxies_priv MODIFY User         CHAR(80)  COLLATE utf8_bin NOT NULL DEFAULT '';
ALTER TABLE mysql.proxies_priv MODIFY Proxied_user CHAR(80)  COLLATE utf8_bin NOT NULL DEFAULT '';
ALTER TABLE mysql.proxies_priv MODIFY Grantor      CHAR(141) COLLATE utf8_bin NOT NULL DEFAULT '';
ALTER TABLE mysql.servers      MODIFY Username     CHAR(80)                   NOT NULL DEFAULT '';
ALTER TABLE mysql.procs_priv   MODIFY Grantor      CHAR(141) COLLATE utf8_bin NOT NULL DEFAULT '';
ALTER TABLE mysql.tables_priv  MODIFY Grantor      CHAR(141) COLLATE utf8_bin NOT NULL DEFAULT '';

FLUSH PRIVILEGES;

Anonymous Accounts

Anonymous accounts are accounts where the user name portion of the account name is empty. These accounts act as special catch-all accounts. If a user attempts to log into the system from a host, and an anonymous account exists with a host name portion that matches the user's host, then the user will log in as the anonymous account if there is no more specific account match for the user name that the user entered.

For example, here are some anonymous accounts:

CREATE USER ''@'localhost';
CREATE USER ''@'192.168.0.3';

Fixing a Legacy Default Anonymous Account

On some systems, the mysql.db table has some entries for the ''@'%' anonymous account by default. Unfortunately, there is no matching entry in the mysql.user table, which means that this anonymous account doesn't exactly exist, but it does have privileges--usually on the default test database created by mysql_install_db. These account-less privileges are a legacy that is leftover from a time when MySQL's privilege system was less advanced.

This situation means that you will run into errors if you try to create a ''@'%' account. For example:

CREATE USER ''@'%';
ERROR 1396 (HY000): Operation CREATE USER failed for ''@'%'

The fix is to DELETE the row in the mysql.db table and then execute FLUSH PRIVILEGES:

DELETE FROM mysql.db WHERE User='' AND Host='%';
FLUSH PRIVILEGES;

And then the account can be created:

CREATE USER ''@'%';
Query OK, 0 rows affected (0.01 sec)

See MDEV-13486 for more information.

See Also

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