12-1

连接mysql数据库

mysql -u root -p 123456

mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| python |
| sys |
+--------------------+
5 rows in set (0.00 sec)

mysql> use mysql;
Database changed

mysql> show tables;
+---------------------------+
| Tables_in_mysql           |
+---------------------------+
| columns_priv              |
| component                 |
| db                        |
| default_roles             |
| engine_cost               |
| func                      |
| general_log               |
| global_grants             |
| gtid_executed             |
| help_category             |
| help_keyword              |
| help_relation             |
| help_topic                |
| innodb_index_stats        |
| innodb_table_stats        |
| password_history          |
| plugin                    |
| procs_priv                |
| proxies_priv              |
| role_edges                |
| server_cost               |
| servers                   |
| slave_master_info         |
| slave_relay_log_info      |
| slave_worker_info         |
| slow_log                  |
| tables_priv               |
| time_zone                 |
| time_zone_leap_second     |
| time_zone_name            |
| time_zone_transition      |
| time_zone_transition_type |
| user                      |
+---------------------------+
33 rows in set (0.02 sec)

mysql> desc user;

mysql> select * from user;

竖列显示，注意后面没有分号
mysql> select * from userG

mysql> quit;

Mysql安装成功后，默认的root用户密码为空，可以使用下面的命令创建root用户的密码：

mysqladmin -u root password "new password"

 创建一个用户

use test;
show tables;
grant all on test.* to 'alex'@'%' identified by 'alex3714'

use mysql;
select * from userG
show grants for alex;