MYSQL_UPGRADE(1)

NAME
mysql_upgrade - check and upgrade MySQL tables

SYNOPSIS

mysql_upgrade [options]

DESCRIPTION

    Note

    As of MySQL 8.0.16, the MySQL server performs the upgrade tasks previously handled by mysql_upgrade (for details, see Section 3.4, “What the MySQL Upgrade Process Upgrades”). Consequently, mysql_upgrade is unneeded and is deprecated as of that version; expect it to be removed in a future version of MySQL. Because mysql_upgrade no longer performs upgrade tasks, it exits with status 0 unconditionally.

Each time you upgrade MySQL, you should execute mysql_upgrade, which looks for incompatibilities with the upgraded MySQL server:

    • It upgrades the system tables in the mysql schema so that you can take advantage of new privileges or capabilities that might have been added.

    • It upgrades the Performance Schema, INFORMATION_SCHEMA, and sys schema.

    • It examines user schemas.

If mysql_upgrade finds that a table has a possible incompatibility, it performs a table check and, if problems are found, attempts a table repair. If the table cannot be repaired, see Section 3.14, “Rebuilding or Repairing Tables or Indexes” for manual table repair strategies.

mysql_upgrade communicates directly with the MySQL server, sending it the SQL statements required to perform an upgrade.

    Caution

    You should always back up your current MySQL installation before performing an upgrade. See Section 9.2, “Database Backup Methods”.

    Some upgrade incompatibilities may require special handling before upgrading your MySQL installation and running mysql_upgrade. See Chapter 3, Upgrading MySQL, for instructions on determining whether any such incompatibilities apply to your installation and how to handle them.

Use mysql_upgrade like this:

    1. Ensure that the server is running.

    2. Invoke mysql_upgrade to upgrade the system tables in the mysql schema and check and repair tables in other schemas:

        mysql_upgrade [options]

    3. Stop the server and restart it so that any system table changes take effect.

If you have multiple MySQL server instances to upgrade, invoke mysql_upgrade with connection parameters appropriate for connecting to each of the desired servers. For example, with servers running on the local host on parts 3306 through 3308, upgrade each of them by connecting to the appropriate port:

    mysql_upgrade --protocol=tcp -P 3306 [other_options]
    mysql_upgrade --protocol=tcp -P 3307 [other_options]
    mysql_upgrade --protocol=tcp -P 3308 [other_options]

For local host connections on Unix, the --protocol=tcp option forces a connection using TCP/IP rather than the Unix socket file.

By default, mysql_upgrade runs as the MySQL root user. If the root password is expired when you run mysql_upgrade, it displays a message that your password is expired and that mysql_upgrade failed as a result. To correct this, reset the root password to unexpire it and run mysql_upgrade again. First, connect to the server as root:

    $> mysql -u root -p
    Enter password: ****  <- enter root password here

Reset the password using ALTER USER:

    mysql> ALTER USER USER() IDENTIFIED BY 'root-password';

Then exit mysql and run mysql_upgrade again:

    $> mysql_upgrade [options]

    Note

    If you run the server with the disabled_storage_engines system variable set to disable certain storage engines (for example, MyISAM), mysql_upgrade might fail with an error like this:

        mysql_upgrade: [ERROR] 3161: Storage engine MyISAM is disabled
        (Table creation is disallowed).

    To handle this, restart the server with disabled_storage_engines disabled. Then you should be able to run mysql_upgrade successfully. After that, restart the server with disabled_storage_engines set to its original value.

Unless invoked with the --upgrade-system-tables option, mysql_upgrade processes all tables in all user schemas as necessary. Table checking might take a long time to complete. Each table is locked and therefore unavailable to other sessions while it is being processed. Check and repair operations can be time-consuming, particularly for large tables. Table checking uses the FOR UPGRADE option of the CHECK TABLE statement. For details about what this option entails, see Section 15.7.3.2, “CHECK TABLE Statement”.

mysql_upgrade marks all checked and repaired tables with the current MySQL version number. This ensures that the next time you run mysql_upgrade with the same version of the server, it can be determined whether there is any need to check or repair a given table again.

mysql_upgrade saves the MySQL version number in a file named mysql_upgrade_info in the data directory. This is used to quickly check whether all tables have been checked for this release so that table-checking can be skipped. To ignore this file and perform the check regardless, use the --force option.

    Note

    The mysql_upgrade_info file is deprecated; expect it to be removed in a future version of MySQL.

mysql_upgrade checks mysql.user system table rows and, for any row with an empty plugin column, sets that column to 'mysql_native_password' if the credentials use a hash format compatible with that plugin. Rows with a pre-4.1 password hash must be upgraded manually.

mysql_upgrade does not upgrade the contents of the time zone tables or help tables. For upgrade instructions, see Section 7.1.15, “MySQL Server Time Zone Support”, and Section 7.1.17, “Server-Side Help Support”.

Unless invoked with the --skip-sys-schema option, mysql_upgrade installs the sys schema if it is not installed, and upgrades it to the current version otherwise. An error occurs if a sys schema exists but has no version view, on the assumption that its absence indicates a user-created schema:

    A sys schema exists with no sys.version view. If
    you have a user created sys schema, this must be renamed for the
    upgrade to succeed.

To upgrade in this case, remove or rename the existing sys schema first.

mysql_upgrade supports the following options, which can be specified on the command line or in the [mysql_upgrade] and [client] groups of an option file. For information about option files used by MySQL programs, see Section 6.2.2.2, “Using Option Files”.

    • --help
    Command-Line Format | --help

    Display a short help message and exit.

    • --bind-address=ip_address
    Command-Line Format | --bind-address=ip_address

    On a computer having multiple network interfaces, use this option to select which interface to use for connecting to the MySQL server.

    • --character-sets-dir=dir_name
    Command-Line Format | --character-sets-dir=dir_name
    Type | Directory name

    The directory where character sets are installed. See Section 12.15, “Character Set Configuration”.

    • --compress, -C
    Command-Line Format | --compress[={OFF|ON}]
    Deprecated | 8.0.18
    Type | Boolean
    Default Value | OFF

    Compress all information sent between the client and the server if possible. See Section 6.2.8, “Connection Compression Control”.

    As of MySQL 8.0.18, this option is deprecated. Expect it to be removed in a future version of MySQL. See the section called “Configuring Legacy Connection Compression”.

    • --compression-algorithms=value
    Command-Line Format | --compression-algorithms=value
    Introduced | 8.0.18
    Type | Set
    Default Value | uncompressed
    Valid Values | zlib zstd uncompressed

    The permitted compression algorithms for connections to the server. The available algorithms are the same as for the protocol_compression_algorithms system variable. The default value is uncompressed.

    For more information, see Section 6.2.8, “Connection Compression Control”.

    This option was added in MySQL 8.0.18.

    • --debug[=debug_options], -# [debug_options]
    Command-Line Format | --debug[=#]
    Type | String
    Default Value | d:t:O,/tmp/mysql_upgrade.trace

    Write a debugging log. A typical debug_options string is d:t:o,file_name. The default is d:t:O,/tmp/mysql_upgrade.trace.

    • --debug-check
    Command-Line Format | --debug-check
    Type | Boolean

    Print some debugging information when the program exits.

    • --debug-info, -T
    Command-Line Format | --debug-info
    Type | Boolean
    Default Value | FALSE

    Print debugging information and memory and CPU usage statistics when the program exits.

    • --default-auth=plugin
    Command-Line Format | --default-auth=plugin
    Type | String

    A hint about which client-side authentication plugin to use. See Section 8.2.17, “Pluggable Authentication”.

    • --default-character-set=charset_name
    Command-Line Format | --default-character-set=name
    Type | String

    Use charset_name as the default character set. See Section 12.15, “Character Set Configuration”.

    • --defaults-extra-file=file_name
    Command-Line Format | --defaults-extra-file=file_name
    Type | File name

    Read this option file after the global option file but (on Unix) before the user option file. If the file does not exist or is otherwise inaccessible, an error occurs. If file_name is not an absolute path name, it is interpreted relative to the current directory.

    For additional information about this and other option-file options, see Section 6.2.2.3, “Command-Line Options that Affect Option-File Handling”.

    • --defaults-file=file_name
    Command-Line Format | --defaults-file=file_name
    Type | File name

    Use only the given option file. If the file does not exist or is otherwise inaccessible, an error occurs. If file_name is not an absolute path name, it is interpreted relative to the current directory.

    For additional information about this and other option-file options, see Section 6.2.2.3, “Command-Line Options that Affect Option-File Handling”.

    • --defaults-group-suffix=str
    Command-Line Format | --defaults-group-suffix=str
    Type | String

    Read not only the usual option groups, but also groups with the usual names and a suffix of str. For example, mysql_upgrade normally reads the [client] and [mysql_upgrade] groups. If this option is given as --defaults-group-suffix=_other, mysql_upgrade also reads the [client_other] and [mysql_upgrade_other] groups.

    For additional information about this and other option-file options, see Section 6.2.2.3, “Command-Line Options that Affect Option-File Handling”.

    • --force
    Command-Line Format | --force
    Type | Boolean

    Ignore the mysql_upgrade_info file and force execution even if mysql_upgrade has already been executed for the current version of MySQL.

    • --get-server-public-key
    Command-Line Format | --get-server-public-key
    Type | Boolean

    Request from the server the public key required for RSA key pair-based password exchange. This option applies to clients that authenticate with the caching_sha2_password authentication plugin. For that plugin, the server does not send the public key unless requested. This option is ignored for accounts that do not authenticate with that plugin. It is also ignored if RSA-based password exchange is not used, as is the case when the client connects to the server using a secure connection.

    If --server-public-key-path=file_name is given and specifies a valid public key file, it takes precedence over --get-server-public-key.

    For information about the caching_sha2_password plugin, see Section 8.4.1.2, “Caching SHA-2 Pluggable Authentication”.

    • --host=host_name, -h host_name
    Command-Line Format | --host=name
    Type | String

    Connect to the MySQL server on the given host.

    • --login-path=name
    Command-Line Format | --login-path=name
    Type | String

    Read options from the named login path in the .mylogin.cnf login path file. A “login path” is an option group containing options that specify which MySQL server to connect to and which account to authenticate as. To create or modify a login path file, use the mysql_config_editor utility. See mysql_config_editor(1).

    For additional information about this and other option-file options, see Section 6.2.2.3, “Command-Line Options that Affect Option-File Handling”.

    • --max-allowed-packet=value
    Command-Line Format | --max-allowed-packet=value
    Type | Integer
    Default Value | 25165824
    Minimum Value | 4096
    Maximum Value | 2147483648

    The maximum size of the buffer for client/server communication. The default value is 24MB. The minimum and maximum values are 4KB and 2GB.

    • --net-buffer-length=value
    Command-Line Format | --net-buffer-length=value
    Type | Integer
    Default Value | 1047552
    Minimum Value | 4096
    Maximum Value | 16777216

    The initial size of the buffer for client/server communication. The default value is 1MB − 1KB. The minimum and maximum values are 4KB and 16MB.

    • --no-defaults
    Command-Line Format | --no-defaults

    Do not read any option files. If program startup fails due to reading unknown options from an option file, --no-defaults can be used to prevent them from being read.

    The exception is that the .mylogin.cnf file is read in all cases, if it exists. This permits passwords to be specified in a safer way than on the command line even when --no-defaults is used. To create .mylogin.cnf, use the mysql_config_editor utility. See mysql_config_editor(1).

    For additional information about this and other option-file options, see Section 6.2.2.3, “Command-Line Options that Affect Option-File Handling”.

    • --password[=password], -p[password]
    Command-Line Format | --password[=name]
    Type | String

    The password of the MySQL account used for connecting to the server. The password value is optional. If not given, mysql_upgrade prompts for one. If given, there must be no space between --password= or -p and the password following it. If no password option is specified, the default is to send no password.

    Specifying a password on the command line should be considered insecure. To avoid giving the password on the command line, use an option file. See Section 8.1.2.1, “End-User Guidelines for Password Security”.

    To explicitly specify that there is no password and that mysql_upgrade should not prompt for one, use the --skip-password option.

    • --pipe, -W
    Command-Line Format | --pipe
    Type | String

    On Windows, connect to the server using a named pipe. This option applies only if the server was started with the named_pipe system variable enabled to support named-pipe connections. In addition, the user making the connection must be a member of the Windows group specified by the named_pipe_full_access_group system variable.

    • --plugin-dir=dir_name
    Command-Line Format | --plugin-dir=dir_name
    Type | Directory name

    The directory in which to look for plugins. Specify this option if the --default-auth option is used to specify an authentication plugin but mysql_upgrade does not find it. See Section 8.2.17, “Pluggable Authentication”.

    • --port=port_num, -P port_num
    Command-Line Format | --port=#
    Type | Numeric

    For TCP/IP connections, the port number to use.

    • --print-defaults
    Command-Line Format | --print-defaults

    Print the program name and all options that it gets from option files.

    • --protocol={TCP|SOCKET|PIPE|MEMORY}
    Command-Line Format | --protocol=name
    Type | String

    The transport protocol to use for connecting to the server. It is useful when the other connection parameters normally result in use of a protocol other than the one you want. For details on the permissible values, see Section 6.2.7, “Connection Transport Protocols”.

    • --server-public-key-path=file_name
    Command-Line Format | --server-public-key-path=file_name
    Type | File name

    The path name to a file in PEM format containing a client-side copy of the public key required by the server for RSA key pair-based password exchange. This option applies to clients that authenticate with the sha256_password or caching_sha2_password authentication plugin. This option is ignored for accounts that do not authenticate with one of those plugins. It is also ignored if RSA-based password exchange is not used, as is the case when the client connects to the server using a secure connection.

    If --server-public-key-path=file_name is given and specifies a valid public key file, it takes precedence over --get-server-public-key.

    For sha256_password, this option applies only if MySQL was built using OpenSSL.

    For information about the sha256_password and caching_sha2_password plugins, see Section 8.4.1.3, “SHA-256 Pluggable Authentication”, and Section 8.4.1.2, “Caching SHA-2 Pluggable Authentication”.

    • --shared-memory-base-name=name
    Command-Line Format | --shared-memory-base-name=name
    Platform Specific | Windows

    On Windows, the shared-memory name to use for connections made using shared memory to a local server. The default value is MYSQL. The shared-memory name is case-sensitive.

    This option applies only if the server was started with the shared_memory system variable enabled to support shared-memory connections.

    • --skip-sys-schema
    Command-Line Format | --skip-sys-schema
    Type | Boolean
    Default Value | FALSE

    By default, mysql_upgrade installs the sys schema if it is not installed, and upgrades it to the current version otherwise. The --skip-sys-schema option suppresses this behavior.

    • --socket=path, -S path
    Command-Line Format | --socket={file_name|pipe_name}
    Type | String

    For connections to localhost, the Unix socket file to use, or, on Windows, the name of the named pipe to use.

    On Windows, this option applies only if the server was started with the named_pipe system variable enabled to support named-pipe connections. In addition, the user making the connection must be a member of the Windows group specified by the named_pipe_full_access_group system variable.

    • --ssl* Options that begin with --ssl specify whether to connect to the server using encryption and indicate where to find SSL keys and certificates. See the section called “Command Options for Encrypted Connections”.

    • --ssl-fips-mode={OFF|ON|STRICT}
    Command-Line Format | --ssl-fips-mode={OFF|ON|STRICT}
    Deprecated | 8.0.34
    Type | Enumeration
    Default Value | OFF
    Valid Values | OFF ON STRICT

    Controls whether to enable FIPS mode on the client side. The --ssl-fips-mode option differs from other --ssl-xxx options in that it is not used to establish encrypted connections, but rather to affect which cryptographic operations to permit. See Section 8.8, “FIPS Support”.

    These --ssl-fips-mode values are permitted:

        • OFF: Disable FIPS mode.

        • ON: Enable FIPS mode.

        • STRICT: Enable “strict” FIPS mode.

        Note
        If the OpenSSL FIPS Object Module is not available, the only permitted value for --ssl-fips-mode is OFF. In this case, setting --ssl-fips-mode to ON or STRICT causes the client to produce a warning at startup and to operate in non-FIPS mode.

    As of MySQL 8.0.34, this option is deprecated. Expect it to be removed in a future version of MySQL.

    • --tls-ciphersuites=ciphersuite_list
    Command-Line Format | --tls-ciphersuites=ciphersuite_list
    Introduced | 8.0.16
    Type | String

    The permissible ciphersuites for encrypted connections that use TLSv1.3. The value is a list of one or more colon-separated ciphersuite names. The ciphersuites that can be named for this option depend on the SSL library used to compile MySQL. For details, see Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”.

    This option was added in MySQL 8.0.16.

    • --tls-version=protocol_list
    Command-Line Format | --tls-version=protocol_list
    Type | String
    Default Value (≥ 8.0.16) | TLSv1,TLSv1.1,TLSv1.2,TLSv1.3 (OpenSSL 1.1.1 or higher) TLSv1,TLSv1.1,TLSv1.2 (otherwise)
    Default Value (≤ 8.0.15) | TLSv1,TLSv1.1,TLSv1.2

    The permissible TLS protocols for encrypted connections. The value is a list of one or more comma-separated protocol names. The protocols that can be named for this option depend on the SSL library used to compile MySQL. For details, see Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”.

    • --upgrade-system-tables, -s
    Command-Line Format | --upgrade-system-tables
    Type | Boolean

    Upgrade only the system tables in the mysql schema, do not upgrade user schemas.

    • --user=user_name, -u user_name
    Command-Line Format | --user=name
    Type | String

    The user name of the MySQL account to use for connecting to the server. The default user name is root.

    • --verbose
    Command-Line Format | --verbose
    Type | Boolean

    Verbose mode. Print more information about what the program does.

    • --version-check, -k
    Command-Line Format | --version-check
    Type | Boolean

    Check the version of the server to which mysql_upgrade is connecting to verify that it is the same as the version for which mysql_upgrade was built. If not, mysql_upgrade exits. This option is enabled by default; to disable the check, use --skip-version-check.

    • --write-binlog
    Command-Line Format | --write-binlog
    Type | Boolean
    Default Value | OFF

    By default, binary logging by mysql_upgrade is disabled. Invoke the program with --write-binlog if you want its actions to be written to the binary log.

    When the server is running with global transaction identifiers (GTIDs) enabled (gtid_mode=ON), do not enable binary logging by mysql_upgrade.

    • --zstd-compression-level=level
    Command-Line Format | --zstd-compression-level=#
    Introduced | 8.0.18
    Type | Integer

    The compression level to use for connections to the server that use the zstd compression algorithm. The permitted levels are from 1 to 22, with larger values indicating increasing levels of compression. The default zstd compression level is 3. The compression level setting has no effect on connections that do not use zstd compression.

    For more information, see Section 6.2.8, “Connection Compression Control”.

    This option was added in MySQL 8.0.18.

COPYRIGHT

Copyright © 1997, 2025, Oracle and/or its affiliates.

This documentation is free software; you can redistribute it and/or modify it only under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License.

This documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with the program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see http://www.gnu.org/licenses/.

SEE ALSO
For more information, please refer to the MySQL Reference Manual, which may already be installed locally and which is also available online at http://dev.mysql.com/doc/.

AUTHOR
Oracle Corporation (http://dev.mysql.com/).