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前言 SQL Server是一种关系型数据库管理系统(RDBMS),由Microsoft开发和维护。它是一款功能强大、稳定可靠的数据库软件,支持事务、数据存储、管理和查询等各种功能,是企业级应用的首选数据库。SQL Server可以在Windows操作系统上运行,并提供了大量的管理工具和API,可以支持多个用户或应用程序同时访问数据库。SQL Server还提供了多种安全功能,包括数据加密、访问控制和身份验证机制等,可以保护数据库的安全性和完整性。此外,SQL Server还支持多种语言和平台,可以方便地与其他应用程序进行集成和交互,可用于各种应用场景,包括Web应用、企业应用、商业智能和数据仓库等。 目录 1 数据库、表的创建与管理 1.1 创建数据库 1.2 创建表 1.3 插入数据 1.4 数据操作 2 数据完整性的设置 2.1 设置外键 2.2 创建unique约束 2.3 创建、删除check约束 2.4 创建、删除规则 3 数据检索 3.1 单表数据查询 3.2 多表查询与子查询 4 索引和视图 4.1 创建索引 4.2 创建视图 4.3 删除索引和视图 5 存储过程和触发器 5.1 创建存储过程 5.2 创建触发器 1 数据库、表的创建与管理 1.1 创建数据库利用SQL Server Management Studio创建一个名为teaching数据库,初始大小为10MB,增长速度为10%,其他均采用默认设置。 在查询编辑器中输入创建表的代码,分别创建student、course、score、teacher、 class、teach_class这6张表 创建student表代码: create table teaching.dbo.student( studentno nchar(11) not null, sname nvarchar(8) null, sex nchar(1) null, birthday datetime null, classno nchar(7) null, point smallint null, phone nchar(12) null, Email nvarchar(20) null, constraint pk_student primary key (studentno asc))创建course表代码: create table teaching.dbo.course( courseno nchar(6) not null, cname nchar(20) null, type nchar(8) null, period tinyint null, credit numeric(4,1) null, constraint pk_course primary key (courseno asc))创建score表和teacher表代码: create table teaching.dbo.score( studentno nchar(11) not null, courseno nchar(6) not null, usually numeric(6,2) null, final numeric(6,2) null, constraint pk_score primary key (studentno asc,courseno asc)) create table teaching.dbo.teacher( teacherno nchar(6) not null, tname nchar(8) null, major nchar(10) null, prof nchar(10) null, department nchar(12) null, constraint pk_teacher primary key (teacherno asc))创建class表、teach_class表代码: create table teaching.dbo.class( classno nchar(7) not null, classname nchar(12) null, department nchar(12) null, monitor nchar(8) null, constraint pk_class primary key (classno asc)) create table teaching.dbo.teach_class( teacherno nchar(6) not null, classno nchar(7) not null, courseno nchar(6) not null, constraint pk_teach_class primary key (teacherno asc,classno asc,courseno asc)) 1.3 插入数据分别对这6张表输入记录(每张表不少于5条记录) 向student表插入数据: Insert into teaching.dbo.student (studentno,sname,sex,birthday,classno,point,phone,Email) Values ('082211120','赵某','男','1989-12-11','1701','101','15200000000','[email protected]') Insert into teaching.dbo.student (studentno,sname,sex,birthday,classno,point,phone,Email) Values ('082211121','余某','男','1989-12-12','1702','102','15211111111','[email protected]') Insert into teaching.dbo.student (studentno,sname,sex,birthday,classno,point,phone,Email) Values ('082211122','程某','女','1989-12-13','1703','103','15222222222','[email protected]') Insert into teaching.dbo.student (studentno,sname,sex,birthday,classno,point,phone,Email) Values ('082211123','周某','男','1989-12-14','1704','104','15233333333','[email protected]') Insert into teaching.dbo.student (studentno,sname,sex,birthday,classno,point,phone,Email) Values ('082211124','霍某','女','1989-12-15','1705','105','15244444444','[email protected]')student 表数据 向course表插入数据: Insert into teaching.dbo.course Values('c05120','数据结构','必修','60','1') Insert into teaching.dbo.course Values('c05121','操作系统','选修','61','2') Insert into teaching.dbo.course Values('c05122','数据逻辑','必修','62','3') Insert into teaching.dbo.course Values('c05123','计算方法','必修','63','4') Insert into teaching.dbo.course Values('c05124','大学体育','选修','64','5')course表数据 向score表插入数据: Insert into teaching.dbo.score Values('0822111201','c06101','89','91') Insert into teaching.dbo.score Values('0822111202','c06102','88','92') Insert into teaching.dbo.score Values('0822111203','c06103','87','93') Insert into teaching.dbo.score Values('0822111204','c06104','86','94') Insert into teaching.dbo.score Values('0822111205','c06105','85','95')score表数据 向teacher表插入数据: Insert into teaching.dbo.teacher Values('t05001','赵某某','数据结构','教授','计算机学院') Insert into teaching.dbo.teacher Values('t05002','余某某','操作系统','教授','计算机学院') Insert into teaching.dbo.teacher Values('t05003','程某某','数据逻辑','教授','经济学院') Insert into teaching.dbo.teacher Values('t05004','周某某','计算方法','导师','计算机学院') Insert into teaching.dbo.teacher Values('t05005','霍某某','大学体育','教授','经济学院')teacher表数据 向class表插入数据: Insert into teaching.dbo.class Values('080601','机械','机械学院','马飞') Insert into teaching.dbo.class Values('080602','机械','机械学院','李飞') Insert into teaching.dbo.class Values('080603','机械','机械学院','张飞') Insert into teaching.dbo.class Values('080604','机械','机械学院','周飞') Insert into teaching.dbo.class Values('080605','机械','机械学院','余飞')class表数据 向teach_class表插入数据: Insert into teaching.dbo.teach_class Values('t05001','080601','c05120') Insert into teaching.dbo.teach_class Values('t05002','080602','c05121') Insert into teaching.dbo.teach_class Values('t05003','080603','c05122') Insert into teaching.dbo.teach_class Values('t05004','080604','c05123') Insert into teaching.dbo.teach_class Values('t05005','080605','c05124')teach_class表数据 向student表插入、删除、修改一条记录 插入一条记录: insert into teaching.dbo.student values('0937221508','平静','女','1998-02-12','1709','109','15299999999','[email protected]')删除一条记录: delete from teaching.dbo.student where studentno='0937221508'修改一条记录: update teaching.dbo.student set point=888 where studentno='0937221508'通过本次实验,我掌握了创建、修改数据库的方法及管理数据库的方法,并掌握了创建、修改表结构的方法及插入、更新和删除表数据的方法,让我对SQL server2008的使用更加得心应手。总而言之,本次实验的内容让我受益匪浅,也为数据库这门课程的学习做了铺垫作用。 2 数据完整性的设置 2.1 设置外键利用SQL Server Management Studio将teaching数据库中score表的courseno列设置为引用表course的外键。 在teaching数据库中class表的classname创建UNIQUE约束。 alter table class add constraint u_classname unique nonclustered(classname) go 2.3 创建、删除check约束为teaching数据库中student表的birthday列创建check约束,规定学生的年龄在17~25之间,为course表的credit列创建check约束,规定学分的取值范围为1~6,删除check约束。 alter table student add constraint ck_birthday check (year(getdate()-year(birthday)) between 17 and 25) go alter table course add constraint ck_credit check(credit>=1 and credit20 (3)查询计算机学院教师的专业名称 select prof from teaching.dbo.teacher where department='计算机学院' (4)查询每名学生的学号、选修课程数目、总成绩,并将查询结果存放到生成的“学生选课统计表” use teaching go if exists (select * from sys.objects where name='学生选课统计表') drop table 学生选课统计表 select studentno,COUNT(*) as '选修课程数目',sum(final) as '总成绩' into 学生选课统计表 from score group by studentno select * from 学生选课统计表 (5)查询student表中所有学生的基本信息,查询结果按班级号classno升序排序,同一班级中的学生按入学成绩point降序排列 select * from teaching.dbo.student order by classno,point desc (6)查询各班学生的人数(按班级分组),查询各班期末成绩的最高分和最低分 select COUNT(*) as '人数',MAX(final) as '最高分', MIN(final) as '最低分' from teaching.dbo.student,teaching.dbo.score where student.studentno=score.studentno group by classno order by classno (7)查询教授一门及以上课程的教师编号、课程编号和任课班级 select teacherno,courseno,classno from teaching.dbo.teach_class where exists (select courseno,COUNT(*) from teaching.dbo.course group by courseno having COUNT(*)>=1)(8)查询课程编号以c05开头,被三名及以上学生选修,且期末成绩的平均分高于75分的课程号、选修人数和期末成绩平均分,并按平均分降序排序。 use teaching go select courseno,count(studentno)as '选修人数',avg(final) as '期末平均分' from score where courseno like 'c06%' and final is not null GROUP BY courseno having COUNT(studentno)>=3 and AVG(final)>75 order by AVG(final) desc 通过本次实验,我掌握了SELECT各个子句的功能和检索数据的方法,掌握WHERE子句中LIKE、IN、BETWEEN、IS等逻辑运算符的使用,掌握了聚合函数的使用,本次实验,编写代码途中出现点小差错,导致运行失败,但经过自己查找资料,最终问题得以解决,让我更加对SQL server的使用游刃有余。希望自己在今后的实验中严谨认真,做好每一次实验。 3.2 多表查询与子查询(1)查询所有班级的期末成绩平均分,并按照平均分降序排序 select classno,AVG(final) from teaching.dbo.score join teaching.dbo.teach_class on score.courseno=teach_class.courseno group by classno order by AVG(final) desc (2)查询教师基本信息和教授课程信息,其中包括未分配课程的教师信息 select teacher.teacherno,tname,major,prof,courseno from teaching.dbo.teacher left join teaching.dbo.teach_class on teacher.teacherno=teach_class.teacherno (3)查询两门及以上课程的期末成绩超过80分的学生姓名及其平均成绩 select sname,AVG(final) from teaching.dbo.score join teaching.dbo.student on score.studentno=student.studentno where exists (select courseno,COUNT(*) from teaching.dbo.score group by courseno having COUNT(*)>=2) and final>80 group by sname (4)查询没有被任何学生选修的课程编号、课程名称和学分(子查询) select courseno,cname,credit from teaching.dbo.course where not exists (select * from teaching.dbo.score where score.courseno=course.courseno) (5)查询入学成绩最高的学生学号、姓名和入学成绩(子查询) select studentno,sname,point from teaching.dbo.student where studentno in (select top 1 studentno from teaching.dbo.student order by point desc) (6)查询同时教授c05120号和c05121号课程的教师信息(子查询) select * from teaching.dbo.teacher left join teaching.dbo.teach_class on teacher.teacherno=teach_class.teacherno where courseno='c05120' and teacher.teacherno in (select teacherno from teaching.dbo.teach_class where courseno='c05121')(7)查询每门课程的课程号、课程名和选修该课程的学生人数,并按所选人数升序排序 select courseno,cname,COUNT(*) from teaching.dbo.course group by courseno,cname order by COUNT(*) (8)使用游标输出学生姓名、选修课程名称和期末考试成绩 declare student_cursor cursor for select sname,cname,final from teaching.dbo.student join teaching.dbo.score on student.studentno=score.studentno join teaching.dbo.course on score.courseno=course.courseno open student_cursor declare @sname nchar(8),@cname nchar(20),@final numeric(6,2) fetch next from student_cursor into @sname,@cname,@final print '学生名字课程名称期末成绩' print'-----------------------' while @@FETCH_STATUS=0 begin print @sname+@cname+cast(@final as nchar(6)) fetch next from student_cursor into @sname,@cname,@final end close student_cursor deallocate student_cursor通过本次实验,我掌握了多表连接的各种方法(内连接和外连接),掌握了子查询的方法(相关子查询和不相关子查询),还有游标处理集的基本过程,会使用JOIN ON连接两个及两个以上表,查询到了表中相关信息,也学会了在SELECT查询语句中再嵌套一个SELECT语句,还学会了使用游标对查询结果集进行处理。总之,本次的多表查询与子查询的实验,我受益匪浅,更坚定了我对这门课程的学习的决心。 4 索引和视图 4.1 创建索引(1)在teaching数据库的student表的classno字段创建非聚集非唯一索引cu_classno create nonclustered index cu_classno on teaching.dbo.student(classno)(2)在teaching数据库中的teacher表的tname列上创建非聚集唯一索引UQ_name ,若该索引已存在,则删除后重建 if exists(select name from sysindexes where name='UQ_name') drop index teacher.UQ_name go create index UQ_name on teaching.dbo.teacher(tname) 4.2 创建视图创建视图步骤: 1.在“对象资源管理器”窗口中展开“数据库”下的teaching子目录。 2.右击“视图”选项,从弹出的快捷菜单中选择“新建视图”命令,进入视图设计页面。 3.同时在弹出的“添加表”对话框中,选择course和score两个表,单击“添加”按钮。 4.点击“添加表”对话框中的“关闭”按钮,返回SQL Server Management Studio的视图设计界面进行设计。
(1)在teaching 数据库中创建视图v_teacher_course,包含教师编号、教师姓名、职称、课程号、课程名和任课班级,通过视图v_teacher_course将教师编号为t05017的教师职称更改为”副教授” create view v_teacher_course as select teacher.teacherno,tname, prof,course.courseno,cname,classno from teaching.dbo.teacher,teaching.dbo.course,teaching.dbo.teach_class where teacher.teacherno=teach_class.teacherno and teach_class.courseno=course.courseno go update v_teacher_course set prof='副教授' where teacherno='t05107' Go(2)修改v_course_avg视图的定义,添加WITH CHECK OPTION选项 alter view v_course_avg as select course.courseno, cname,AVG(final) as avg from teaching.dbo.course,teaching.dbo.score group by course.courseno,cname having AVG(final)>80 with check option 4.3 删除索引和视图 drop index cu_classno on teaching.dbo.student drop view v_course_avg通过本次实验,我通过创建索引理解什么是聚集和非聚集,什么是唯一索引,在course表创建、删除视图,给视图添加条件约束。在实验中,创建视图总显示CREATE VIEW必须是批处理中仅有的语句,导致运行失败,经过资料的查询,可能是在这段代码之前还有其他语句是同时处理,需要在这段代码的开始和结束加一个GO才行,最终问题也成功解决,也弥补了自己对SQL server使用的盲区。 5 存储过程和触发器 5.1 创建存储过程(1)创建一个存储过程ProcNum,查询每个班级中学生的人数,按班级号升序排序 create proc procnum as select classno, COUNT(*) as 人数 from teaching.dbo.student group by classno order by classno asc(2)利用SQL语句创建一个带有参数的存储过程ProcInsert,向score表插入一条选课记录,并查询该学生的姓名、选修的所有课程名称、平时成绩和期末成绩 create proc ProcInsert @sna nvarchar(255),@cna nvarchar(255), @final float,@usually float as insert into teaching.dbo.score values(@sna,@cna,@final,@usually) select sname,cname,usually, final from teaching.dbo.student join teaching.dbo.score on student.studentno=score.studentno join teaching.dbo.course on course.courseno=score.courseno(3)利用SQL语句创建一个存储过程ProcAvg,查询指定课程的平均分。班级号和课程名称由输入参数确定,计算出的平均分通过输出参数返回,若该存储过程已存在,则删除后重建 if exists (select * from sysobjects where name='procavg') drop proc procavg go create proc procavg @classno nvarchar(255),@cname nvarchar(255), @average float output as select @average=AVG(final*0.8+usually*0.2) from teaching.dbo.student join teaching.dbo.score on student.studentno=score.studentno join teaching.dbo.course on course.courseno=score.courseno where classno=@classno and cname=@cname 5.2 创建触发器(1)创建一个AFTER触发器trigsex,当插入或修改student表中性别字段sex时,检查数据是否只为“男”或“女” use teaching go create trigger trigsex on teaching.dbo.student after insert,update as begin declare @sex nvarchar(255) select @sex=sex from teaching.dbo.student if @sex='男' or @sex='女' begin raiserror('性别只能为男或女', 16,2)(2)利用SQL语句创建一个AFTER触发器trigforeign,当向score表中插入或修改记录时,如果插入或修改的数据与student表中数据不匹配,即没有对应的学号存在,则将此记录删除 use teaching go create trigger trigforeign on score after insert ,update as begin declare @studentno nvarchar(255) select @studentno=studentno from teaching.dbo.score if not exists (select * from student where studentno=@studentno) begin raiserror('不能插入学号不存在的学生的信息',16,2) end end(3)利用SQL语句创建一个AFTER触发器trigclassname,当向class表中插入或修改数据时,如果出现班级名称重复则回滚事务,若该触发器已存在,则删除后重建 if exists (select * from sysobjects where name='trigclassname') drop trigger trigclassname go use teaching go create trigger trigclassname on class after insert,update as begin declare @classname nvarchar(255) select @classname=classname from class if exists (select classname from class) begin raiserror('班级名称不能重复',16,2) rollback end end通过本次实验,我掌握了创建、管理存储过程的方法,并学会创建AFTER触发器,当重复则回滚事务,如果触发器存在则删除触发器。在实验中,创建触发器时,不知道为什么一直出现“对象不存在或对此操作无效”的提示,最后经过查找资料才知需要在前面加入“use go”代码才可以,最后问题也迎之而解,SQL Server方面的知识也更加全面。 |
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