harvey@harvey-Virtual-Machine:~/ruby/mydiary$ mysql -u root -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.

mysql> show databases; --注意必须要用;结尾否则不会立即执行代码
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mydiary            |
| mysql              |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)

mysql> use mysql #mysql是数据库自带的
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
mysql> show tables
    -> ;
+---------------------------+
| Tables_in_mysql           |
+---------------------------+
| columns_priv              |
| db                        |
| event                     |
| func                      |
| general_log               |
| help_category             |
| help_keyword              |
| help_relation             |
| help_topic                |
| host                      |
| ndb_binlog_index          |
| plugin                    |
| proc                      |
| procs_priv                |
| proxies_priv              |
| servers                   |
| slow_log                  |
| tables_priv               |
| time_zone                 |
| time_zone_leap_second     |
| time_zone_name            |
| time_zone_transition      |
| time_zone_transition_type |
| user                      | #这里是mysql的所有用户
+---------------------------+
24 rows in set (0.00 sec)