//请输入班级人数,输入每个人的学号,姓名,和语文分数.数学分数和英语分数(要求使用结构体), //求班级里两个语文分数是最高分的学生的所有信息:数学分数是最高分的两个学生的所有信息:英语平均分 建立结构体 class Program { struct student { public int xuehao ; public string name; public score score; } struct score { public double yufen; public double s
1.先写一个Student类 public class Student { private String name; private int chinese; private int math; private int english; public Student() { super(); } public Student(String name, int chinese, int math, int english) { this.name = name; this.chinese = ch
方法1: 查出科目成绩有小于80分的学生姓名,再约束并去重学生不等于查出来的姓名 select distinct A.name from t_score A where A.name not in(select distinct B.name from t_score B where B.fenshu <=80) 方法2: 按学生姓名分组,且最小的分数要大于80分 select A.name from t_score A group by A.name having min(A.fenshu)>
create table test (id int, name ), score int, classname )); ,,'一班'); ,,'一班'); ,,'一班'); ,,'二班'); ,,'二班'); ,,'二班'); select t.* from (select test.*,row_number() over (partition by classname order by score desc) rn from test) t ;
任务:有学生,科目,考分三张表,需要从中筛选出五门考分总和超过720的学生. 科目表最简单只有五条记录: CREATE TABLE tb_course ( id NUMBER not null primary key, name NVARCHAR2(10) not null ) Insert into tb_course(id,name) values('','语文'); Insert into tb_course(id,name) values('','数学'); Insert into tb
************************************************************ * 标题:MS SQLServer 批量附加数据库 * 说明:请根据下面的注释使用此脚本 * 时间: 2015/7/13 11:16:41 ************************************************************/ USE MASTER GO IF OBJECT_ID('[sp_AttchDataBase]') IS NOT N
数学函数.字符串函数.转换函数.时间日期函数 1.数学函数 ceiling()--取上限 select ceiling(oil) as 油耗上限 from car floor()--取下限 select floor(oil) as 油耗下限 from car ) as 四舍五入 from car (两个参数) select)--为保留一位小数 select abs(-10)--绝对值 select PI()--圆周率 select sqrt()--开根号 select square()--平方
1创建表 create database Mathgouse MathgoCREATE TABLE A(ID INT PRIMARY KEY IDENTITY,--自增主键ID_CARD VARCHAR(18) NOT NULL,--身份证编号Person_Type VARCHAR(3) NOT NULL,--是否在职Fee_Date DATETIME NOT NULL,--开销时间Fee_Amount DECIMAL(18,2) NOT NULL--开销金额)goINSERT INTO A V
PARTII: SQL Basics CHAPTER 4Creating a Simple Query 介绍一种怎样创建SQL语句的技术--"Request/Translation/CleanUp/SQL" The SELECT operation in SQL can be broken down into three smaller operations, which we will refer to as the SELECT statement,the SELECT expre
PART I:Relational Databases and SQL Chapter2, Ensuring Your Database Structure IsSound. 数据库设计准则 什么是关系数据库 RDBMS (A Relational database management systems)关系数据库 Tables Tables are the mainstructures in the database. Each table always represents a single
CHAPTER 5 Getting More Than Simple Columns Intro Value expression,it contains column names, literal values, functions, or other value expressions The type of data The SQL Standard defines seven general categories of types of data-character, national