Options that affect security: See Section 5.3.3, “Security-Related mysqld Options”.

SSL-related options: See Section 5.5.7.3, “SSL Command Options”.

Binary log control options: See Section 5.2.3, “The Binary Log”.

Replication-related options: See Section 18.1.2, “Replication Startup Options and Variables”.

Options specific to particular storage engines: See Section 13.1.1, “MyISAM Startup Options”, Section 13.5.3, “BDB Startup Options”, Section 13.2.4, “InnoDB Startup Options and System Variables”, and Section 19.4.2, “MySQL Cluster-Related Command Options for mysqld”.

--help, -?

Display a short help message and exit. Use both the --verbose and --help options to see the full message.

--abort-slave-event-count

When this option is set to some positive integer value other than 0 (the default) it affects replication behavior as follows: After the slave SQL thread has started, value log events are allowed to be executed; after that, the slave SQL thread does not receive any more events, just as if the network connection from the master were cut. The slave thread continues to run, and the output from SHOW SLAVE STATUS displays Yes in both the Slave_IO_Running and the Slave_SQL_Running columns, but no further events are read from the relay log.

This option is used internally by the MySQL test suite for replication testing and debugging. It is not intended for use in a production setting.

--allow-suspicious-udfs

This option controls whether user-defined functions that have only an xxx symbol for the main function can be loaded. By default, the option is off and only UDFs that have at least one auxiliary symbol can be loaded; this prevents attempts at loading functions from shared object files other than those containing legitimate UDFs. This option was added in version 5.0.3. See Section 28.2.2.6, “User-Defined Function Security Precautions”.

--ansi

Use standard (ANSI) SQL syntax instead of MySQL syntax. For more precise control over the server SQL mode, use the --sql-mode option instead. See Section 1.8.3, “Running MySQL in ANSI Mode”, and Section 5.1.7, “SQL Modes”.

--basedir=path, -b path

The path to the MySQL installation directory. All paths are usually resolved relative to this directory.

--big-tables

Allow large result sets by saving all temporary sets in files. This option prevents most “table full” errors, but also slows down queries for which in-memory tables would suffice. Since MySQL 3.23.2, the server is able to handle large result sets automatically by using memory for small temporary tables and switching to disk tables where necessary.

--bind-address=IP

The IP address to bind to. Only one address can be selected. If this option is specified multiple times, the last address given is used.

--bootstrap

This option is used by the mysql_install_db script to create the MySQL privilege tables without having to start a full MySQL server.

This option is unavailable if MySQL was configured with the --disable-grant-options option. See Section 2.4.15.2, “Typical configure Options”.

--character-sets-dir=path

The directory where character sets are installed. See Section 9.2, “The Character Set Used for Data and Sorting”.

--character-set-client-handshake

Don't ignore character set information sent by the client. To ignore client information and use the default server character set, use --skip-character-set-client-handshake; this makes MySQL behave like MySQL 4.0.

--character-set-filesystem=charset_name

The filesystem character set. This option sets the character_set_filesystem system variable. It was added in MySQL 5.0.19.

--character-set-server=charset_name, -C charset_name

Use charset_name as the default server character set. See Section 9.2, “The Character Set Used for Data and Sorting”. If you use this option to specify a non-default character set, you should also use --collation-server to specify the collation.

--chroot=path, -r path

Put the mysqld server in a closed environment during startup by using the chroot() system call. This is a recommended security measure. Note that use of this option somewhat limits LOAD DATA INFILE and SELECT ... INTO OUTFILE.

--collation-server=collation_name

Use collation_name as the default server collation. See Section 9.2, “The Character Set Used for Data and Sorting”.

--console

(Windows only.) Write error log messages to stderr and stdout even if --log-error is specified. mysqld does not close the console window if this option is used.

--core-file

Write a core file if mysqld dies. For some systems, you must also specify the --core-file-size option to mysqld_safe. See Section 4.3.2, “mysqld_safe — MySQL Server Startup Script”. Note that on some systems, such as Solaris, you do not get a core file if you are also using the --user option.

--datadir=path, -h path

The path to the data directory.

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

If MySQL is configured with --with-debug, you can use this option to get a trace file of what mysqld is doing. The debug_options string often is 'd:t:o,file_name'. The default is 'd:t:i:o,mysqld.trace'. See MySQL Internals: Porting.

As of MySQL 5.0.25, using --with-debug to configure MySQL with debugging support enables you to use the --debug="d,parser_debug" option when you start the server. This causes the Bison parser that is used to process SQL statements to dump a parser trace to the server's standard error output. Typically, this output is written to the error log.

--default-character-set=charset_name (DEPRECATED)

Use charset_name as the default character set. This option is deprecated in favor of --character-set-server. See Section 9.2, “The Character Set Used for Data and Sorting”.

--default-collation=collation_name

Use collation_name as the default collation. This option is deprecated in favor of --collation-server. See Section 9.2, “The Character Set Used for Data and Sorting”.

--default-storage-engine=type

Set the default storage engine (table type) for tables. See Chapter 13, Storage Engines.

--default-table-type=type

This option is a synonym for --default-storage-engine.

--default-time-zone=timezone

Set the default server time zone. This option sets the global time_zone system variable. If this option is not given, the default time zone is the same as the system time zone (given by the value of the system_time_zone system variable.

--delay-key-write[={OFF|ON|ALL}]

Specify how to use delayed key writes. Delayed key writing causes key buffers not to be flushed between writes for MyISAM tables. OFF disables delayed key writes. ON enables delayed key writes for those tables that were created with the DELAY_KEY_WRITE option. ALL delays key writes for all MyISAM tables. See Section 7.5.2, “Tuning Server Parameters”, and Section 13.1.1, “MyISAM Startup Options”.

--des-key-file=file_name

Read the default DES keys from this file. These keys are used by the DES_ENCRYPT() and DES_DECRYPT() functions.

--disconnect-slave-event-count

This option is used internally by the MySQL test suite for replication testing and debugging.

--enable-named-pipe

Enable support for named pipes. This option can be used only with the mysqld-nt and mysqld-debug servers that support named-pipe connections.

--enable-pstack

Print a symbolic stack trace on failure.

--engine-condition-pushdown={ON|OFF}

When the value of this option is 0 (OFF), a query such as SELECT * FROM t WHERE mycol = 42, where mycol is a non-indexed column, is executed as a full table scan. The storage engine sends every row to the MySQL server, which applies the WHERE condition. If engine_condition_pushdown is set to 1 (ON), the condition is “pushed down” to the storage engine, which uses the condition to perform the scan, and sends back to the MySQL server only those rows that match the condition. By default, this variable is OFF.

In MySQL 5.0, this option is useful only with the NDBCLUSTER storage engine. However, we intend to implement it for additional storage engines in future MySQL releases.

Setting this option to ON on a MySQL Server acting as a MySQL Cluster SQL node causes WHERE conditions on unindexed columns to be evaluated on the cluster's data nodes and only the rows that match to be sent back to the SQL node that issued the query. This means the amount of cluster data that must be sent over the network is greatly reduced, increasing the efficiency with which results are returned.

For more information, see Section 7.2.7, “Condition Pushdown Optimization”.

This variable was added in MySQL 5.0.3.

--exit-info[=flags], -T [flags]

This is a bit mask of different flags that you can use for debugging the mysqld server. Do not use this option unless you know exactly what it does!

--external-locking

Enable external locking (system locking), which is disabled by default as of MySQL 4.0. Note that if you use this option on a system on which lockd does not fully work (such as Linux), it is easy for mysqld to deadlock. This option previously was named --enable-locking.

For more information about external locking, including conditions under which it can and cannot be used, see Section 7.3.4, “External Locking”.

--flush

Flush (synchronize) all changes to disk after each SQL statement. Normally, MySQL does a write of all changes to disk only after each SQL statement and lets the operating system handle the synchronizing to disk. See Section B.1.4.2, “What to Do If MySQL Keeps Crashing”.

--gdb

Install an interrupt handler for SIGINT (needed to stop mysqld with ^C to set breakpoints) and disable stack tracing and core file handling. See MySQL Internals: Porting.

--init-file=file_name

Read SQL statements from this file at startup. Each statement must be on a single line and should not include comments.

This option is unavailable if MySQL was configured with the --disable-grant-options option. See Section 2.4.15.2, “Typical configure Options”.

--innodb-safe-binlog

Adds consistency guarantees between the content of InnoDB tables and the binary log. See Section 5.2.3, “The Binary Log”. This option was removed in MySQL 5.0.3, having been made obsolete by the introduction of XA transaction support.

--innodb-xxx

The InnoDB options are listed in Section 13.2.4, “InnoDB Startup Options and System Variables”.

--language=lang_name, -L lang_name