CREATE DATABASE qwe; create table Students ( Sno char(12), Sname VARCHAR(20) not null, Ssex char(2), Syear smallint, Sdept varchar(20) )charset=utf8; CREATE table Courses ( Cno char(8), Cname VARCHAR(20) not null, PreCno VARCHAR(30), Credit char(4) )charset=utf8; create TABLE SC ( Sno char(12), cno char(8), Score char(8) )charset=utf8; INSERT into students VALUES("200201","张三","男",2001,"人工智能学院"); INSERT into students VALUES("200202","李四","男",2002,"人工智能学院"); INSERT into students VALUES("200203","王五","女",2003,"计算机学院"); INSERT into students VALUES("200204","赵六","男",2000,"计算机学院"); INSERT into students VALUES("200205","孙琦","女",2002,"经管学院"); INSERT into students VALUES("200206","刘八","男",2001,"经管学院"); INSERT into students VALUES("200207","曾九","女",2002,"美术学院"); INSERT into students VALUES("200208","陈拾","女",2004,"美术学院"); SELECT * from Students; INSERT into courses VALUES("1001","数据库","程序设计基础","3"); INSERT into courses VALUES("1002","大学语文",null,"2"); INSERT into courses VALUES("1003","高等数学",null,"3"); INSERT into courses VALUES("1004","数据结构",null,"3"); INSERT into courses VALUES("1005","计算机导论",null,"3"); INSERT into courses VALUES("1006","计算机网络",null,"4"); INSERT into courses VALUES("1007","程序设计基础",null,"5"); INSERT into courses VALUES("1008","Java","数据结构","5"); SELECT * from courses; INSERT into SC VALUES("200201","1001","90"); INSERT into SC VALUES("200201","1002","85"); INSERT into SC VALUES("200202","1001","85"); INSERT into SC VALUES("200203","1002","75"); INSERT into SC VALUES("200202","1002","55"); INSERT into SC VALUES("200202","1003","95"); INSERT into SC VALUES("200206","1007","65"); INSERT into SC VALUES("200204","1008","77"); INSERT into SC VALUES("200205","1004","89"); INSERT into SC VALUES("200208","1007","45"); SELECT * from courses; 运行以上SQL代码前提下,查询最高分同学的学号,查询张三同学所有选修课程的总成绩
时间: 2023-06-28 17:11:03 浏览: 53
查询最高分同学的学号:
```
SELECT Sno FROM SC WHERE Score = (SELECT MAX(Score) FROM SC);
```
查询张三同学所有选修课程的总成绩:
```
SELECT SUM(Score) FROM SC WHERE Sno = '200201';
```
相关问题
如何把名为frame的(char*),变为名为QWE的frameDataIn 对象
假设你的frame是一个字符数组,可以按照以下步骤将其转换为QWE类型的frameDataIn对象:
1. 创建一个QWE类型的变量,例如:QWE qwe;
2. 将frame数据复制到QWE对象的缓冲区中,可以使用memcpy函数实现,例如:memcpy(qwe.buffer, frame, sizeof(frame));
3. 设置QWE对象的其他属性,例如QWE对象的长度属性length,可以将其设置为frame长度,例如:qwe.length = sizeof(frame);
4. 现在你已经成功将frame转换为QWE类型的frameDataIn对象了。
CREATE TABLE `admin` ( `admin_id` int(11) NOT NULL AUTO_INCREMENT, `admin_name` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL, `admin_number` int(11) NOT NULL, PRIMARY KEY (`admin_id`) USING BTREE ) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC; insert into `admin`(`admin_id`,`admin_name`,`admin_password`) values (1,'zxc','123',),(2,'qwe','123',);这段语句有什么错误
这段语句有两个错误:
1. `admin_number` 字段在 CREATE TABLE 语句中被定义,但在 INSERT INTO 语句中没有被插入值,这会导致插入失败。你可能想要将它更改为 `admin_password` 字段。
2. 在 INSERT INTO 语句中,最后一个插入值后面有一个额外的逗号,这会导致插入失败。你需要将 `(1,'zxc','123',)` 和 `(2,'qwe','123',)` 中的逗号删除。
下面是修改后的语句:
```
CREATE TABLE `admin` (
`admin_id` int(11) NOT NULL AUTO_INCREMENT,
`admin_name` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
`admin_password` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
PRIMARY KEY (`admin_id`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC;
INSERT INTO `admin`(`admin_id`, `admin_name`, `admin_password`)
VALUES (1, 'zxc', '123'), (2, 'qwe', '123');
```
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