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 2.11.4, "Rebuilding or Repairing Tables or Indexes" for manual table repair strategies.

You should execute mysql_upgrade each time you upgrade MySQL.

If you install MySQL from RPM packages on Linux, you must install the server and client RPMs. mysql_upgrade is included in the server RPM but requires the client RPM because the latter includes mysqlcheck. (See Section 2.5.5, "Installing MySQL on Linux Using RPM Packages from Oracle".)

Note

On Windows Server 2008, Vista, and newer, you must run mysql_upgrade with administrator privileges. You can do this by running a Command Prompt as Administrator and running the command. Failure to do so may result in the upgrade failing to execute correctly.

Caution

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 you upgrade your MySQL installation and run mysql_upgrade. See Section 2.11.1, "Upgrading MySQL", for instructions on determining whether any such incompatibilities apply to your installation and how to handle them.

To use mysql_upgrade, make sure that the server is running. Then invoke it like this:

shell> mysql_upgrade [options]

After running mysql_upgrade, stop the server and restart it so that any changes made to the system tables take effect.

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

shell> mysql_upgrade --protocol=tcp -P 3306 [other_options]
shell> mysql_upgrade --protocol=tcp -P 3307 [other_options]
shell> 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.

mysql_upgrade executes the following commands to check and repair tables and to upgrade the system tables:

mysqlcheck --no-defaults --databases
 --fix-db-names --fix-table-names mysql
mysqlcheck --no-defaults --check-upgrade --databases
 --auto-repair mysql
mysql < fix_priv_tables
mysqlcheck --no-defaults --all-databases
 --skip-database=mysql --fix-db-names --fix-table-names
mysqlcheck --no-defaults --check-upgrade --all-databases
 --skip-database=mysql --auto-repair

Notes about the preceding commands:

• mysql_upgrade also adds --write-binlog or --skip-write-binlog to the mysqlcheck commands, depending on whether the --write-binlog option was specified on the mysql_upgrade command.

• Because mysql_upgrade invokes mysqlcheck with the --all-databases option, it processes all tables in all databases, which 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.

• For details about what checks the --check-upgrade option entails, see the description of the FOR UPGRADE option of the CHECK TABLE statement (see Section 13.7.2.2, "CHECK TABLE Syntax").

• fix_priv_tables represents a script generated internally by mysql_upgrade that contains SQL statements to upgrade the tables in the mysql database.

All checked and repaired tables are marked with the current MySQL version number. This ensures that next time you run mysql_upgrade with the same version of the server, it can tell whether there is any need to check or repair the table again.

mysql_upgrade also 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.

mysql_upgrade does not upgrade the contents of the help tables. For upgrade instructions, see Section 5.1.10, "Server-Side Help".

By default, mysql_upgrade runs as the MySQL root user. If the root password is expired when you run mysql_upgrade, you will see 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:

shell> mysql -u root -p
Enter password: ****  <- enter root password here
mysql> SET PASSWORD = PASSWORD('root-password');
mysql> quit
shell> mysql_upgrade [options]

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. Unrecognized options are passed to mysqlcheck. For information about option files, see Section 4.2.6, "Using Option Files".

• --help

Display a short help message and exit.

• --basedir=dir_name

The path to the MySQL installation directory. This option is accepted for backward compatibility but ignored. It is removed in MySQL 5.7.

• --character-sets-dir=dir_name

The directory where character sets are installed. See Section 10.5, "Character Set Configuration".

• --compress

Compress all information sent between the client and the server if both support compression.

• --datadir=dir_name

The path to the data directory. This option is accepted for backward compatibility but ignored. It is removed in MySQL 5.7.

• --debug[=debug_options], -# [debug_options]

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

Print some debugging information when the program exits.

• --debug-info, -T

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

• --default-auth=plugin

A hint about the client-side authentication plugin to use. See Section 6.3.7, "Pluggable Authentication".

This option was added in MySQL 5.6.2.

• --default-character-set=charset_name

Use charset_name as the default character set. See Section 10.5, "Character Set Configuration".

• --defaults-extra-file=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. file_name is interpreted relative to the current directory if given as a relative path name rather than a full path name.

• --defaults-file=file_name

Use only the given option file. If the file does not exist or is otherwise inaccessible, an error occurs. file_name is interpreted relative to the current directory if given as a relative path name rather than a full path name.

• --defaults-group-suffix=str

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 the --defaults-group-suffix=_other option is given, mysql_upgrade also reads the [client_other] and [mysql_upgrade_other] groups.

• --force

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

• --host=host_name, -h host_name

Connect to the MySQL server on the given host.

• --login-path=name

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). This option was added in MySQL 5.6.6.

• --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, if it exists, is read in all cases. This permits passwords to be specified in a safer way than on the command line even when --no-defaults is used. (.mylogin.cnf is created by the mysql_config_editor utility. See mysql_config_editor(1).)

• --password[=password], -p[password]

The password to use when connecting to the server. If you use the short option form (-p), you cannot have a space between the option and the password. If you omit the password value following the --password or -p option on the command line, mysql_upgrade prompts for one.

Specifying a password on the command line should be considered insecure. See Section 6.1.2.1, "End-User Guidelines for Password Security". You can use an option file to avoid giving the password on the command line.

• --pipe, -W

On Windows, connect to the server using a named pipe. This option applies only if the server supports named-pipe connections.

• --plugin-dir=dir_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 6.3.7, "Pluggable Authentication".

This option was added in MySQL 5.6.2.

• --port=port_num, -P port_num

The TCP/IP port number to use for the connection.

• --print-defaults

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

• --protocol={TCP|SOCKET|PIPE|MEMORY}

The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the permissible values, see Section 4.2.2, "Connecting to the MySQL Server".

• --shared-memory-base-name=name

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.

The server must be started with the --shared-memory option to enable shared-memory connections.

• --socket=path, -S path

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

• --ssl*

Options that begin with --ssl specify whether to connect to the server using SSL and indicate where to find SSL keys and certificates. See Section 6.3.9.5, "Command Options for Secure Connections".

• --tmpdir=dir_name, -t dir_name

The path name of the directory to use for creating temporary files.

• --upgrade-system-tables, -s

Upgrade only the system tables, do not upgrade data.

• --user=user_name, -u user_name

The MySQL user name to use when connecting to the server. The default user name is root.

• --verbose

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

• --version-check, -k

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. This option was added in MySQL 5.6.12.

• --write-binlog

Cause binary logging to be enabled while mysql_upgrade runs. In MySQL 5.6.6 and earlier, this was the default behavior. (To disable binary logging during the upgrade, it was necessary to use the inverse of this option, by starting the program with --skip-write-binlog.) Beginning with MySQL 5.6.7, binary logging by mysql_upgrade is disabled by default (Bug #14221043). Invoke the program explicitly with --write-binlog if you want its actions to be written to the binary log. (Also beginning with MySQL 5.6.7, the --skip-write-binlog option effectively does nothing.)

Running mysql_upgrade is not recommended with a MySQL Server that is running with global transaction identifiers enabled (Bug #13833710). This is because enabling GTIDs means that any updates which mysql_upgrade might need to perform on system tables using a nontransactional storage engine such as MyISAM to fail. See Section 17.1.3.4, "Restrictions on Replication with GTIDs", for more information.