退出数据库：exit
mysql> exit
取消命令执行：ctrl+c
显示当前连接用户：select user();
mysql> select user();
+----------------+
| user() |
+----------------+
| root@localhost | #当前用户为root用户
+----------------+
1 row in set (0.00 sec)
mysql>
查看数据库服务的基本信息：status;
--------------
mysql Ver 14.14 Distrib 5.7.24, for linux-glibc2.12 (x86_64) using EditLine wrapper
Connection id: 2 #连接的ID号
Current database: #目前用的数据库，目前没有进入任何数据库内
Current user: root@localhost #连接的用户为root
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 5.7.24 MySQL Community Server (GPL) #用的版本为MYSQL5.7.24版本
Protocol version: 10
Connection: Localhost via UNIX socket #连接方式
Server characterset: latin1
Db characterset: latin1
Client characterset: utf8 #字符集
Conn. characterset: utf8
UNIX socket: /tmp/mysql.sock #sock文件存放位置
Uptime: 40 min 37 sec #启动的时间
Threads: 1 Questions: 7 Slow queries: 0 Opens: 105 Flush tables: 1 Open tables: 98 Queries per second avg: 0.002
--------------
查看当前服务器有哪儿些数据库：show databases;
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
4 rows in set (0.08 sec) #4表示有4个库，一个库就是一个目录
查看数据库中的数据表信息：use mysql
mysql> use sys
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed #此时已在sys数据库中
mysql> select databases(); #查看sys数据库中的信息
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'databases()' at line 1
mysql> select database();
+------------+
| database() |
+------------+
| sys |
+------------+
1 row in set (0.00 sec)