linux下MySQL安装与删除 (Ubuntu下)

1、MySQL安装

A）MySQL安装：    sudo apt-get install mysql-server mysql-client　 

B）启动/停止MySQL服务：

      MySQL 在安装以后，MySQL 就已经启动；如果需要手动启动或停止则如下操作：

      手动启动服务：       sudo start mysql  

      手动停止服务：       sudo stop mysql

      当修改mysql相关配置的时候，需要手动重启MySQL服务，就需要如上操作。

      查看mysql进程是否已经启动：

      

ps  -aux  |  grep  mysql 

       #ps -aux 显示当前所有进程(包括 mysql , 和 name 用户 )，  grep mysql 用来查找 mysql 进程 ；具体使用可以查看 ps,  grep 用法

       #man  ps              ;     man  grep

或者使用：

sudo netstat -tap | grep mysql

 两种命令的结果：

 

name@ThinkPad:~$ ps -aux | grep mysql
Warning: bad ps syntax, perhaps a bogus '-'? See http://procps.sf.net/faq.html
mysql      25994  0.0  0.9 137800 18400 ?        Ssl  10:18   0:10 /usr/sbin/mysqld
name       26543  0.0  0.1   8544  2320 pts/2    S+   11:06   0:00 mysql -u root -p
name       27068  0.0  0.1   8388  2064 pts/1    S+   18:21   0:00 mysql -u root -p
name       27917  0.0  0.0   5412   788 pts/3    S+   21:45   0:00 grep --color=auto mysql


name@ThinkPad:~$ sudo netstat -tap | grep mysql
tcp        0      0 localhost:mysql         *:*                     LISTEN      25994/mysqld 

 

C）MySQL 配置文件结构：

      MySQL 配置文件为 my.cnf , 位置在 /etc/my.cnf       以及   /etc/mysql/my.cnf

      

#
# The MySQL database server configuration file.
#
# You can copy this to one of:
# - "/etc/mysql/my.cnf" to set global options,
# - "~/.my.cnf" to set user-specific options.
# 
# One can use all long options that the program supports.
# Run program with --help to get a list of available options and with
# --print-defaults to see which it would actually understand and use.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html

# This will be passed to all mysql clients
# It has been reported that passwords should be enclosed with ticks/quotes
# escpecially if they contain "#" chars...
# Remember to edit /etc/mysql/debian.cnf when changing the socket location.
[client]
port		= 3306
socket		= /var/run/mysqld/mysqld.sock

# Here is entries for some specific programs
# The following values assume you have at least 32M ram

# This was formally known as [safe_mysqld]. Both versions are currently parsed.
[mysqld_safe]
socket		= /var/run/mysqld/mysqld.sock
nice		= 0

[mysqld]
#
# * Basic Settings
#

#
# * IMPORTANT
#   If you make changes to these settings and your system uses apparmor, you may
#   also need to also adjust /etc/apparmor.d/usr.sbin.mysqld.
#

user		= mysql
socket		= /var/run/mysqld/mysqld.sock
port		= 3306
basedir		= /usr
datadir		= /var/lib/mysql
tmpdir		= /tmp
skip-external-locking
#
# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
bind-address		= 127.0.0.1
#
# * Fine Tuning
#
key_buffer		= 16M
max_allowed_packet	= 16M
thread_stack		= 192K
thread_cache_size       = 8
# This replaces the startup script and checks MyISAM tables if needed
# the first time they are touched
myisam-recover         = BACKUP
#max_connections        = 100
#table_cache            = 64
#thread_concurrency     = 10
#
# * Query Cache Configuration
#
query_cache_limit	= 1M
query_cache_size        = 16M
#
# * Logging and Replication
#
# Both location gets rotated by the cronjob.
# Be aware that this log type is a performance killer.
# As of 5.1 you can enable the log at runtime!
#general_log_file        = /var/log/mysql/mysql.log
#general_log             = 1

log_error                = /var/log/mysql/error.log

# Here you can see queries with especially long duration
#log_slow_queries	= /var/log/mysql/mysql-slow.log
#long_query_time = 2
#log-queries-not-using-indexes
#
# The following can be used as easy to replay backup logs or for replication.
# note: if you are setting up a replication slave, see README.Debian about
#       other settings you may need to change.
#server-id		= 1
#log_bin			= /var/log/mysql/mysql-bin.log
expire_logs_days	= 10
max_binlog_size         = 100M
#binlog_do_db		= include_database_name
#binlog_ignore_db	= include_database_name
#
# * InnoDB
#
# InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/.
# Read the manual for more InnoDB related options. There are many!
#
# * Security Features
#
# Read the manual, too, if you want chroot!
# chroot = /var/lib/mysql/
#
# For generating SSL certificates I recommend the OpenSSL GUI "tinyca".
#
# ssl-ca=/etc/mysql/cacert.pem
# ssl-cert=/etc/mysql/server-cert.pem
# ssl-key=/etc/mysql/server-key.pem



[mysqldump]
quick
quote-names
max_allowed_packet	= 16M

[mysql]
#no-auto-rehash	# faster start of mysql but no tab completition

[isamchk]
key_buffer		= 16M

#
# * IMPORTANT: Additional settings that can override those from this file!
#   The files must end with '.cnf', otherwise they'll be ignored.
#
!includedir /etc/mysql/conf.d/

   在启动MySQL的时候会通过读取配置文件my.cnf ，并根据这个文件的路径： /var/run/mysqld/mysqld.sock 启动MySQL

　datadir = /var/lib/mysql  #这句是数据库所在位置，比如如果创建一个数据库mysql_first，则数据库文件放置在该目录下。

 

    log_error = /var/log/mysql/error.log  # mysql错误文件，如果在执行mysql出错了，可以查看该文件。

 

D）进入MySQL

      进入MySQL一般需要密码， 除非使用 safe_mysql

      如果不提供密码则会出现如下错误提示：

ERROR 1045 (28000): Access denied for user 'name'@'localhost' (using password: NO)

      这是因为在安装MySQL输入了密码，需要提供密码；

      具体：

 

name@ThinkPad:~$ sudo mysql -u root -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 40
Server version: 5.1.58-1ubuntu1 (Ubuntu)

Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
This software comes with ABSOLUTELY NO WARRANTY. This is free software,
and you are welcome to modify and redistribute it under the GPL v2 license

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> 

      sudo mysql -u root -p  # 这里的几个参数:  u 表示 user ,后面是参数；  p 表示 password ,会在后面有 Enter password: 提示

      也可以直接提供用户和密码(使用 -- )   

      sudo mysql --user=root  --password=123456

 

C）退出MySQL

      主要有三种方式：

　　mysql> exit
　　Bye

　　mysql> quit
　　Bye

       mysql> #直接按Ctrl + D

 

 

2、卸载MySQL

A）卸载MySQL软件

sudo apt-get autoremove --purge mysql-server-5.1
sudo apt-get remove mysql-server
sudo apt-get autoremove mysql-server
sudo apt-get remove mysql-common 

    

sudo apt-get autoremove --purge mysql-server-5.1 # 中 mysql-server-5.1是系统安装的 mysql-server版本

B）清理其他数据

dpkg -l |grep ^rc|awk '{print $2}' |sudo xargs dpkg -P

 

注： 具体MySQL相关操作的学习在后续文章中出现。