-- 查看当前数据库

mysql> SELECT DATABASE();+------------+| DATABASE() |+------------+| mydb       |+------------+1 row in set (0.00 sec)

 

-- 显示当前时间、用户名、数据库版本

mysql> SELECT now(), user(), version();+---------------------+----------------+-----------+| now()               | user()         | version() |+---------------------+----------------+-----------+| 2019-01-03 15:54:47 | root@localhost | 5.7.24    |+---------------------+----------------+-----------+1 row in set (0.00 sec)

-- 查看已有库

mysql> SHOW DATABASES;+--------------------+| Database           |+--------------------+| information_schema || mydb               || mysql              || performance_schema || sys                |+--------------------+5 rows in set (0.00 sec)

-- 查看当前库信息

mysql> SHOW CREATE DATABASE mydb;+----------+-----------------------------------------------------------------+| Database | Create Database                                                 |+----------+-----------------------------------------------------------------+| mydb     | CREATE DATABASE `mydb` /*!40100 DEFAULT CHARACTER SET latin1 */ |+----------+-----------------------------------------------------------------+1 row in set (0.00 sec)

-- 删除库

mysql> drop database mytest;Query OK, 0 rows affected (0.00 sec)

 启动方式一：

mysqld_safe --secure-file-priv= --user=mysql &

启动方式二：

/etc/init.d/mysqld start

/etc/init.d/mysqld stop

启动方式三：

service mysqld start

service mysqld stop