linux下安装mysql

1.首先在linux系统下载mysql5.7的安装包

$ cd /home/
$ wget https://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-5.7.19-linux-glibc2.12-x86_64.tar.gz

2.建立一个用户组

$ sudo groupadd mysql

3.新建一个mysql用户加入该组

$ sudo useradd -r -g  mysql mysql

4.在home目录下解压mysql安装包

$tar -zxvf mysql-5.7.19-linux-glibc2.12-x86_64.tar.gz

5.将解压之后的文件改名为mysql 放到 /opt下边

$ mv mysql-5.7.19-linux-glibc2.12-x86_64 /opt/mysql

6.进入到/opt/mysql目录下更改权限

$ chown -R  mysql:mysql ./

7.安装辅助的库文件，当然不是必须的看你系统中是不是有

$ sudo apt-get intall libaio1

7.在/etc目录下创建文件my.cnf，并且填写设置内容

$ cd /etc
$ touch my.cnf
$ vi my.cnf

[mysqld]
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
explicit_defaults_for_timestamp=true
basedir = /opt/mysql
datadir = /data/mysql
port = 3306
socket = /opt/mysql/mysqld/mysql.sock
pid-file = /opt/mysql/mysqld/mysql.pid
character-set-server=utf8
back_log = 300
max_connections = 3000
max_connect_errors = 50
table_open_cache = 4096
max_allowed_packet = 32M
max_heap_table_size = 128M
read_rnd_buffer_size = 16M
sort_buffer_size = 16M
join_buffer_size = 16M
thread_cache_size = 16
query_cache_size = 128M
query_cache_limit = 4M
ft_min_word_len = 8
thread_stack = 512K
transaction_isolation = REPEATABLE-READ
tmp_table_size = 128M
long_query_time = 6
server_id=1
innodb_buffer_pool_size = 1G
innodb_thread_concurrency = 16
innodb_log_buffer_size = 16M
innodb_log_file_size = 512M
innodb_log_files_in_group = 3
innodb_max_dirty_pages_pct = 90
innodb_lock_wait_timeout = 120
innodb_file_per_table = on
[mysqldump]
quick
max_allowed_packet = 32M
[mysql]
no-auto-rehash
default-character-set=utf8
safe-updates
[myisamchk]
key_buffer = 16M
sort_buffer_size = 16M
read_buffer = 8M
write_buffer = 8M
[mysqlhotcopy]
interactive-timeout
[mysqld_safe]
open-files-limit = 8192
[client]
port = 3306
socket = /opt/mysql/mysqld/mysql.sock
default-character-set = utf8

9、创建文件夹/data/mysql，/opt/mysql/mysqld

$ mkdir -p /data/mysql
$ chown -R mysql:mysql /data/mysql
$ chmod -R 755 /data/mysql
$ mkdir -p /opt/mysql/mysqld
$ chown -R mysql:mysql /opt/mysql/mysqld
$ chmod -R 755 /opt/mysql/mysqld

10、到解压的mysql目录中找到bin ，在bin中有 mysqld 可执行文件。执行

$ ./mysqld --user=mysql --basedir=/opt/mysql --datadir=/data/mysql --initialize

generated for root@localhost: dsuIequSe5>E

由上面信息可得：dsuIequSe5>E （为root用户的临时登录密码）

11.配置系统环境变量

$vim /etc/profile

MYSQL_HOME=/opt/mysql/bin
PATH=$MYSQL_HOME/bin:$PATH
export MYSQL_HOME

12.连接数据库

$mysql -u root -p

    密码：步骤10中生成的零时密码
    mysql> set password=password('你的新密码');

13.window下的navicat连接linux的mysql

```

可能会出现ERROR 1130 (HY000): Host ‘xxx.xxx.xxx.xxx’ is not allowed to connect to this MySQL server
解决办法：
改mysql的user表，具体方法如下：
1、先用use mysql;进入名字为mysql的数据库；
2、mysql>update user set host='%' where host='localhost' and user='root';
3、mysql>flush privileges;
4、使用查询语句查看是否修改过来：mysql>select host,user from user;

5、出现%就可以连上了