入门级sql语句运用

• 显示数据库语法
• 新建数据库语法
• 使用数据库语法
• 显示表语法
• 查询表语法

显示数据库语法

语法：show databases；

mysql> show databases;
+----------------------+
| Database             |
+----------------------+
| information_schema   |
| jdbc_xiangyang_liao1 |
| my_jdbc              |
| myfirstdb            |
| mysql                |
| performance_schema   |
| sys                  |
+----------------------+
7 rows in set (0.02 sec)

新建数据库语法

语法：create database 库名；

mysql> create database new_cre;
Query OK, 1 row affected (0.01 sec)

mysql> show databases;
+----------------------+
| Database             |
+----------------------+
| information_schema   |
| jdbc_xiangyang_liao1 |
| my_jdbc              |
| myfirstdb            |
| mysql                |
| new_cre              |
| performance_schema   |
| sys                  |
+----------------------+
8 rows in set (0.00 sec)

使用数据库语法

语法：use 库名；

mysql> use my_jdbc;
Database changed

显示表语法

语法：show tables；

mysql> show tables;
+-------------------+
| Tables_in_my_jdbc |
+-------------------+
| my_jd             |
| my_jdbc           |
| student           |
| ww                |
| www               |
| wwwww             |
+-------------------+
6 rows in set (0.01 sec)

查询表语法

语法：select * from 表名；

mysql> select * from my_jdbc;
+------+----+------+
| name | id | pass |
+------+----+------+
| w    |  1 |  111 |
+------+----+------+
1 row in set (0.01 sec)