4.4.5 mysql_upgrade — Check and Upgrade MySQL Tables

Note注意

As of MySQL 8.0.16, the MySQL server performs the upgrade tasks previously handled by mysql_upgrade (for details, see Section 2.11.3, “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:

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 2.11.13, “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小心

You should always back up your current MySQL installation before performing an upgrade. See Section 7.2, “Database Backup Methods”.

Some upgrade incompatibilities may require special handling before upgrading your MySQL installation and running mysql_upgrade. See Section 2.11, “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:

shell> 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:

shell> mysql_upgrade [options]
Note注意

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 13.7.3.2, “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注意

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 5.1.15, “MySQL Server Time Zone Support”, and Section 5.1.17, “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 4.2.2.2, “Using Option Files”.

Table 4.10 mysql_upgrade Options

Option NameDescriptionIntroducedDeprecated
--bind-addressUse specified network interface to connect to MySQL Server
--character-sets-dirDirectory where character sets are installed
--compressCompress all information sent between client and server8.0.18
--compression-algorithmsPermitted compression algorithms for connections to server8.0.18
--debugWrite debugging log
--debug-checkPrint debugging information when program exits
--debug-infoPrint debugging information, memory, and CPU statistics when program exits
--default-authAuthentication plugin to use
--default-character-setSpecify default character set
--defaults-extra-fileRead named option file in addition to usual option files
--defaults-fileRead only named option file
--defaults-group-suffixOption group suffix value
--forceForce execution even if mysql_upgrade has already been executed for current MySQL version
--get-server-public-keyRequest RSA public key from server
--helpDisplay help message and exit
--hostHost on which MySQL server is located
--login-pathRead login path options from .mylogin.cnf
--max-allowed-packetMaximum packet length to send to or receive from server
--net-buffer-lengthBuffer size for TCP/IP and socket communication
--no-defaultsRead no option files
--passwordPassword to use when connecting to server
--pipeConnect to server using named pipe (Windows only)
--plugin-dirDirectory where plugins are installed
--portTCP/IP port number for connection
--print-defaultsPrint default options
--protocolTransport protocol to use
--server-public-key-pathPath name to file containing RSA public key
--shared-memory-base-nameShared-memory name for shared-memory connections (Windows only)
--skip-sys-schemaDo not install or upgrade sys schema
--socketUnix socket file or Windows named pipe to use
--ssl-caFile that contains list of trusted SSL Certificate Authorities
--ssl-capathDirectory that contains trusted SSL Certificate Authority certificate files
--ssl-certFile that contains X.509 certificate
--ssl-cipherPermissible ciphers for connection encryption
--ssl-crlFile that contains certificate revocation lists
--ssl-crlpathDirectory that contains certificate revocation-list files
--ssl-fips-modeWhether to enable FIPS mode on client side
--ssl-keyFile that contains X.509 key
--ssl-modeDesired security state of connection to server
--tls-ciphersuitesPermissible TLSv1.3 ciphersuites for encrypted connections8.0.16
--tls-versionPermissible TLS protocols for encrypted connections
--upgrade-system-tablesUpdate only system tables, not user schemas
--userMySQL user name to use when connecting to server
--verboseVerbose mode
--version-checkCheck for proper server version
--write-binlogWrite all statements to binary log
--zstd-compression-levelCompression level for connections to server that use zstd compression8.0.18