#change root user's password for mysql
mysqladmin -u root -h localhost password 'new_password'

# Alternatively you can run:
/usr/bin/mysql_secure_installation

# which will also give you the option of removing the test databases and anonymous user created by default.  This is strongly recommended for production servers.

# login with root user
mysql -u root -h localhost

# import a *.sql into one database
mysql -uroot -p dbname <src.sql

# show databases
show databases;

# create user sa via any host by using password '123456'
create user 'sa'@'%' identified by '123456';

# grant all privileges for user sa on JESS database
grant all privileges on JESS.* to 'sa'@'%' with grant option;

# show grants for user
show grants for 'sa'@'%';

# delete user, the user's related previliges will be revoked
drop user 'sa'@'%';

# show variables
show variables like "%character%";
# custom parameter setting, set timeout to 1 year (in seconds)
# in /etc/my.cnf, under [mysqld]
wait_timeout = 31536000
interactive_timeout = 31536000

# create database
create database db;

# delete database
drop database db;

# specified key was too long problem, character set -> utf8
test@linux-uv0s:~/Download/JESS-Setup/SQLFiles> mysql -uroot -p testagms <back_mysql_test2.sql
Enter password:
ERROR 1071 (42000) at line 4: Specified key was too long; max key length is 1000 bytes

# show create table command
show create table AttendanceRecord;

# show engines
show engines;

# change default engine
# config file format, /etc/my.cnf
default-storage-engine=InnoDB
# command line format
--default-storage-engine=InnoDB

#change root user's password for mysql
mysqladmin -u root -h localhost password 'new_password'

# Alternatively you can run:
/usr/bin/mysql_secure_installation

# which will also give you the option of removing the test databases and anonymous user created by default.  This is strongly recommended for production servers.

# login with root user
mysql -u root -h localhost

# import a *.sql into one database
mysql -uroot -p dbname <src.sql

# show databases
show databases;

# create user sa via any host by using password '123456'
create user 'sa'@'%' identified by '123456';

# grant all privileges for user sa on JESS database
grant all privileges on JESS.* to 'sa'@'%' with grant option;

# show grants for user
show grants for 'sa'@'%';

# delete user, the user's related previliges will be revoked
drop user 'sa'@'%';

# show variables
show variables like "%character%";
# custom parameter setting, set timeout to 1 year (in seconds)
# in /etc/my.cnf, under [mysqld]
wait_timeout = 31536000
interactive_timeout = 31536000

# create database
create database db;

# delete database
drop database db;

# specified key was too long problem, character set -> utf8
test@linux-uv0s:~/Download/JESS-Setup/SQLFiles> mysql -uroot -p testagms <back_mysql_test2.sql
Enter password:
ERROR 1071 (42000) at line 4: Specified key was too long; max key length is 1000 bytes

# show create table command
show create table AttendanceRecord;

# show engines
show engines;

# change default engine
# config file format, /etc/my.cnf
default-storage-engine=InnoDB
# command line format
--default-storage-engine=InnoDB

删除 mysql
sudo apt-get autoremove --purge mysql-server-5.0
sudo apt-get remove mysql-server
sudo apt-get autoremove mysql-server
sudo apt-get remove mysql-common //这个很重要
上面的其实有一些是多余的。

清理残留数据

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




安装 mysql

sudo apt-get install mysql-server
sudo apt-get install mysql-client
sudo apt-get install php5-mysql
// 安装php5-mysql 是将php和mysql连接起来
一旦安装完成，MySQL 服务器应该自动启动。您可以在终端提示符后运行以下命令来检查 MySQL 服务器是否正在运行：
sudo netstat -tap | grep mysql

当您运行该命令时，您可以看到类似下面的行：
tcp 0 0 localhost.localdomain:mysql *:* LISTEN -

如果服务器不能正常运行，您可以通过下列命令启动它：
sudo /etc/init.d/mysql restart

进入mysql

$mysql -uroot -p 管理员密码


配置 MySQL 的管理员密码：
sudo mysqladmin -u root password newpassword