SQL语句的基本使用1(数据库的进入、表的查询、插入数据)

创建数据库studentsdb

create database studentsdb;

进入数据库studentsdb

use studentsdb;

创建数据表student_info，curriculum，grade

    ->create table student_info(
       学号 char(4) primary key,
    -> 姓名 char(8) ,
    -> 性别 char(2) null,
    -> 出生日期 date null,
    -> 家庭地址 varchar(50) null);

    ->create table curriculum( 
    课程编号 char(4) primary key,
    -> 课程名称 varchar(50) null,
    -> 学分 int null);

    ->create table grade( 
    学号 char(4),
    -> 课程编号 char(4),
    -> 分数 int null,
    -> primary key(学号,课程编号));

    ->insert into student_info( 学号,姓名,性别,出生日期,家庭地址)
      values
    -> ('0001','张青平','男','2000-10-01','衡阳市东风路77号'),
    -> ('0002','刘东阳','男','1998-12-09','东阳市八一北路33号'),
    -> ('0003','马晓夏','女','1995-05-12','长岭市五一路763号'),
    -> ('0004','钱忠理','男','1994-09-23','滨海市洞庭大道279号'),
    -> ('0005','孙海洋','男','1995-04-03','长岛市解放路27号'),
    -> ('0006','郭小斌','男','1997-11-10','南山市红旗路113号'),
    -> ('0007','肖月玲','女','1996-12-07','东方市南京路11号'),
    -> ('0008','张玲珑','女','1997-12-24','滨江市新建路97号');

       insert into curriculum (课程编号,课程名称,学分)
    -> values
    -> ('0001','计算机应用基础','2'),
    -> ('0002','C语言程序设计','2'),
    -> ('0003','数据库原理及应用','2'),
    -> ('0004','英语','4'),
    -> ('0005','高等数学','4');![image-20230918175548597](C:\Users\杨金龙\AppData\Roaming\Typora\typora-user-images\image-20230918175548597.png)

       insert into grade (学号,课程编号,分数)
    -> values
    -> ('0001','0001','80'),
    -> ('0001','0002','91'),
    -> ('0001','0003','88'),
    -> ('0001','0004','85'),
    -> ('0001','0005','77'),
    -> ('0002','0001','73'),
    -> ('0002','0002','68'),
    -> ('0002','0003','80'),
    -> ('0002','0004','79'),
    -> ('0002','0005','73'),
    -> ('0003','0001','84'),
    -> ('0003','0002','92'),
    -> ('0003','0003','81'),
    -> ('0003','0004','82'),
    -> ('0003','0005','75');![image-20230918180617111](C:\Users\杨金龙\AppData\Roaming\Typora\typora-user-images\image-20230918180617111.png)