Ubuntu下的MySQL安装

<1>安装mysql-server

sudo apt-get update
sudo apt-get install mysql-server mysql-client

<2>如何判断mysql是否安装成功

sudo service mysql restart

<3>让apache支持mysql

sudo apt-get install libapache2-mod-auth-mysql

16.04使用下面命令

sudo apt-get install libmysqlclient-dev

<3>登录mysql

mysql -u root -p

<4>配置文件my.cnf修改成功后就可以重启数据库（修改方法在下面），重启数据库之前需要先重新载入apparmor配置文件，使用下面命令重新载入：

sudo /etc/init.d/apparmor restart

　　重新启动数据库

sudo /etc/init.d/mysql start

<5>查看数据库的编码

一、查看MySQL数据库服务器和数据库MySQL字符集。

SHOW VARIABLES LIKE 'character_set_%';

如果需要修改的话

set character_set_client=utf8;

二、查看MySQL数据表（table）的MySQL字符集，spring_user是数据库的名字，t_user是表名

mysql> show table status from spring_user like '%t_user%';

或者

mysql> show create table t_user;

修改方法：

alter table t_user convert to character set utf8;

三、查看MySQL数据列（column）的MySQL字符集，t_user是表名

mysql> show full columns from t_user;

<6>sudo gedit /etc/my.cnf

因为ubuntu下mySQL默认的数据库的路径是在/var/lib/mysql，所以要修改这个路径的话，参考

http://www.2cto.com/database/201501/373939.html

注意修改的时候/mysql要加上

修改的my.cnf文件，修改完切记一定要重启电脑才能生效！！重启电脑！！重启电脑！！

#
# 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
default-character-set=utf8

# 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]
default-character-set=utf8
character_set_server = utf8
socket		= /var/run/mysqld/mysqld.sock
nice		= 0

[mysqld]
#
# * Basic Settings
#
user		= mysql
pid-file	= /var/run/mysqld/mysqld.pid
socket		= /var/run/mysqld/mysqld.sock
character_set_server=utf8
init_connect='SET NAMES utf8'
port		= 3306
basedir		= /usr
datadir		= /home/common/software/database/mysql
tmpdir		= /tmp
lc-messages-dir	= /usr/share/mysql
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
#
# Error log - should be very few entries.
#
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]
default-character-set=utf8
#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/

Ubuntu下Eclipse部署MySQL JDBC驱动

参考http://www.linuxidc.com/Linux/2011-10/44355.htm中的上半部分

Linux下自动启动MySQL

　　

一、查看MySQL数据库服务器和数据库MySQL字符集。

命令：

mysql> show variables like '%char%';

二、查看MySQL数据表（table）的MySQL字符集。

命令：

mysql> show table status from sqlstudy_db like '%countries%';

三、查看MySQL数据列（column）的MySQL字符集。

命令：

mysql> show full columns from countries;

四、修改MySQL的密码

首先用root登录MySQL，然后执行

UPDATE user SET password=PASSWORD('123456') WHERE user='root';
FLUSH PRIVILEGES;

或者

SET PASSWORD FOR 'root'@'localhost' = PASSWORD('newpass');

如果要安装5.6版本的mysql

sudo add-apt-repository 'deb http://archive.ubuntu.com/ubuntu trusty universe'
sudo apt-get update
sudo apt install mysql-server-5.6 mysql-client-5.6

如果卸载5.7再安装的时候遇到

/var/cache/apt/archives/mysql-server-5.6_5.6.16-1~exp1_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)

sudo apt-get remove --purge mysql-server mysql-client mysql-common
sudo apt-get autoremove
sudo apt-get autoclean

先确保 mysql service是启动的,没启动会报找不到mysqld.sock

service mysql status
service mysql start