mysql_upgrade examines all tables in all databases for incompatibilities with the current version of MySQL Server. mysql_upgrade also upgrades the system tables so that you can take advantage of new privileges or capabilities that might have been added.
mysql_upgrade should be executed each time you upgrade MySQL. It supersedes the older mysql_fix_privilege_tables script, which should no longer be used.
If a table is found to have a possible incompatibility, mysql_upgrade performs a table check. If any problems are found, a table repair is attempted. If the table cannot be repaired, see Section 2.12.4, “Rebuilding or Repairing Tables or Indexes” for manual table repair strategies.
You should always back up your current MySQL installation before performing an upgrade. See Section 6.1, “Database Backups”.
Some upgrade incompatibilities may require special handling before you upgrade your MySQL installation and run mysql_upgrade. See Section 2.12.1, “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, and 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.
mysql_upgrade executes the following commands to check and repair tables and to upgrade the system tables:
mysqlcheck --all-databases --check-upgrade --auto-repair
mysql < fix_priv_tables
mysqlcheck --all-databases --check-upgrade --fix-db-names --fix-table-names
Notes about the preceding commands:
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 12.5.2.3, “CHECK TABLE
Syntax”).
fix_priv_tables
represents a
script generated interally by
mysql_upgrade that contains SQL
statements to upgrade the tables in the
mysql
database.
Prior to MySQL 5.1.31, mysql_upgrade does
not run the second mysqlcheck command,
which is necessary to re-encode database or table names that
contain nonalphanumeric characters. (They still appear after
the upgrade with the #mysql50#
prefix
described in Section 8.2.3, “Mapping of Identifiers to File Names”.) If you
have such database or table names, execute the second
mysqlcheck command manually after
executing mysql_upgrade.
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.
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 2.4, “Installing MySQL from RPM Packages on Linux”.)
In MySQL 5.1.7, mysql_upgrade was added as a shell script and worked only for Unix systems. As of MySQL 5.1.10, mysql_upgrade is an executable binary and is available on all systems.
mysql_upgrade supports the options in the
following list. It also reads option files (the
[mysql_upgrade]
and
[client]
groups) and supports the options for
processing them described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”. Other options are passed
to mysqlcheck. For example, it might be
necessary to specify the
--password[=
option.
password
]
Display a short help message and exit.
The path to the MySQL installation directory. This option is accepted for backward compatibility but ignored.
The path to the data directory. This option is accepted for backward compatibility but ignored.
Print some debugging information when the program exits. This option was added in MySQL 5.1.21.
--debug-info
,
-T
Print debugging information and memory and CPU usage statistics when the program exits. This option was added in MySQL 5.1.21.
Ignore the mysql_upgrade_info
file and
force execution of mysqlcheck even if
mysql_upgrade has already been executed
for the current version of MySQL.
--tmpdir=
,
path
-t
path
The path name of the directory to use for creating temporary files. This option was added in MySQL 5.1.25.
--user=
,
user_name
-u
user_name
The MySQL user name to use when connecting to the server.
The default user name is root
.
Verbose mode. Print more information about what the program does.
User Comments
Be careful when you have multiple instances of mysqld running on the same box.
mysql_upgrade reads the sections [mysql_upgrade] and [client] for default values. The values required for an update, notably datadir and friends, are in [mysqld], though. Thus, it will touch the default datadir in /var/lib/mysql as it will not see your special datadir.
You cannot copy my.cnf and rename [mysqld] to [mysql_upgrade], because mysql_upgrade chokes on all the mysqld options. Instead filter the options you need like this:
( echo '[mysql_upgrade]';
$PATHTO/my_print_defaults
--defaults-file=$PATHTO/my.cnf mysqld |
egrep '(datadir|basedir|user|password|socket)' |
sed -e 's/^--//';
) >> $PATHTO/my.cnf
Now mysqld_upgrade will find the information necessary to run properly. Check with
mysql_upgrade --defaults-file=$PATHTO/my.cnf --print-defaults
then run with
mysql_upgrade --defaults-file=$PATHTO/my.cnf -v
If you are running multiple instances of MySQL, then you need to use the port number or socket name in the options list otherwise mysqlcheck will just check the default data directory.
E.g. if you have three instances of MySQL on port 3306, 3307 and 3308, you would need to run mysql_upgrade three times:
shell>mysql_upgrade -P3306 [options]
shell>mysql_upgrade -P3307 [options]
shell>mysql_upgrade -P3308 [options]
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