增删改查

发布时间 2023-11-13 09:51:02作者: q_7

 

数据库的一些操作:

一:数据库的操作

1:创建数据库

语法格式:

create database 数据库名;

  

mysql> create database test;
Query OK, 1 row affected (0.00 sec)

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

mysql> 

  

2:删除数据库

语法格式:

drop database 数据库名;

 

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

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

mysql> 

  

二:表的操作

1:创建表

格式:

create table 表名(字段1[],字段2[]);

eg:

mysql> create table test1(id int,name char(20));
Query OK, 0 rows affected (0.02 sec)

mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| test1          |
+----------------+
1 row in set (0.00 sec)

mysql> 

  

2:删除表

格式:

drop table 表名;

  

eg:

mysql> drop table test1;
Query OK, 0 rows affected (0.01 sec)

mysql> show tables;
Empty set (0.00 sec)

mysql> 

  

三:增删改查的操作 

就是针对的是数据库的数据,而不是数据库的结构

1:增加数据

格式:

insert into 表名 values(值1,值2);

eg:

mysql> insert into test1 values(1,"zhangsan");
Query OK, 1 row affected (0.00 sec)

mysql> select * from test1;
+------+----------+
| id   | name     |
+------+----------+
|    1 | zhangsan |
+------+----------+
1 row in set (0.00 sec)

mysql>

二:修改数据