mysql相关命令的作用总结

1.mysql_config 获取mysql的编译设置

root@nick:/usr/local/mysql/scripts# ./mysql_config

Usage: ./mysql_config [OPTIONS]

Options:

--cflags [-I/usr/local/mysql/include -g]

--include [-I/usr/local/mysql/include]

--libs [-L/usr/local/mysql/lib -lmysqlclient -lpthread -lm -lrt -ldl]

--libs_r [-L/usr/local/mysql/lib -lmysqlclient_r -lpthread -lm -lrt -ldl]

--plugindir [/usr/local/mysql/lib/plugin]

--socket [/tmp/mysqld.sock]

--port [0]

--version [5.5.28]

--libmysqld-libs [-L/usr/local/mysql/lib -lmysqld]

--variable=VAR VAR is one of:

pkgincludedir [/usr/local/mysql/include]

pkglibdir [/usr/local/mysql/lib]

plugindir [/usr/local/mysql/lib/plugin]

2.mysqld_safe 脚本会在启动MySQL服务器后继续监控其运行情况，并在其死机时重新启动它

root@nick:/usr/local/mysql/scripts# ./mysqld_safe --help

Usage: ./mysqld_safe [OPTIONS]

--no-defaults Don't read the system defaults file

--defaults-file=FILE Use the specified defaults file

--defaults-extra-file=FILE Also use defaults from the specified file

--ledir=DIRECTORY Look for mysqld in the specified directory

--open-files-limit=LIMIT Limit the number of open files

--core-file-size=LIMIT Limit core files to the specified size

--timezone=TZ Set the system timezone

--malloc-lib=LIB Preload shared library LIB if available

--mysqld=FILE Use the specified file as mysqld

--mysqld-version=VERSION Use "mysqld-VERSION" as mysqld

--nice=NICE Set the scheduling priority of mysqld

--plugin-dir=DIR Plugins are under DIR or DIR/VERSION, if

VERSION is given

--skip-kill-mysqld Don't try to kill stray mysqld processes

--syslog Log messages to syslog with 'logger'

--skip-syslog Log messages to error log (default)

--syslog-tag=TAG Pass -t "mysqld-TAG" to 'logger'

3.mysql_install_db

当MySQL的系统库（mysql系统库）发生故障或需要新加一个mysql实例时，需要初始化mysql数据库。

需要使用的命令：/usr/local/mysql/bin/mysql_install_db

#/usr/local/mysql/bin/mysql_install_db --help 可以查看帮助信息如下

Usage: /usr/local/mysql/bin/mysql_install_db [OPTIONS]

--basedir=path The path to the MySQL installation directory.

--cross-bootstrap For internal use. Used when building the MySQL system

tables on a different host than the target.

--datadir=path The path to the MySQL data directory.

--force Causes mysql_install_db to run even if DNS does not

work. In that case, grant table entries that normally

use hostnames will use IP addresses.

--ldata=path The path to the MySQL data directory.

--rpm For internal use. This option is used by RPM files

during the MySQL installation process.

--skip-name-resolve Use IP addresses rather than hostnames when creating

grant table entries. This option can be useful if

your DNS does not work.

--srcdir=path For internal use. The directory under which

mysql_install_db looks for support files such as the

error message file and the file for popoulating the

help tables.

--user=user_name The login username to use for running mysqld. Files

and directories created by mysqld will be owned by this

user. You must be root to use this option. By default

mysqld runs using your current login name and files and

directories that it creates will be owned by you.

All other options are passed to the mysqld program

除了支持以上的参数，还支持mysqld的参数。

mysqldump 是采用SQL级别的备份机制，它将数据表导成 SQL 脚本文件，数据库大时，占用系统资源较多，支持常用的MyISAM，innodb

mysqlhotcopy只是简单的缓存写入和文件复制的过程，占用资源和备份速度比mysqldump快很多很多。特别适合大的数据库，但需要注意的是：mysqlhotcopy只支持MyISAM 引擎