添加30条数据(3)求每门课的平均成绩,并把结果存入average表;解:USEh:\数据库实验作业二\实验二\score表.dbfEXCLUSIVEselescore表.Cno,avg(score表.score)as平均分;fromscore表;intotableaverage;groupbyscore表.CnoBrowse截图:(4)将学生“马丽鹃”的出生日期改为“1982.8.20”;解:USEh:\数据库实验作业二\实验二\student表.dbfEXCLUSIVEeditforsname='马丽娟'截图:(5)将所有学生的zipcode属性列值填补上;解:replZipcodewith230006replallZipcodewith230006USEh:\student.dbfEXCLUSIVEmodifystructurereplallZipcodewith230006截图:(6)将average表中的所有课程的平均成绩置零;解:USEh:\数据库实验作业二\实验二\average.dbfEXCLUSIVEreplall平均分with0截图:(7)删除average表中的课程号为‘c007’的平均成绩记录;解:USEh:\数据库实验作业二\实验二\average.dbfEXCLUSIVEdeleteforCno='C007'browsepackBrowse截图:(8)删除所有average表中平均成绩记录;解:deleteallpackbrowse截图:(9)建立一个临时学生信息表(tstudent),删除该表中的学号前六位为‘001011’的所有学生记录。解:Select*;fromstudent;intocursortstudent;wheresubstr(Sno,1,6)!='001011'browse截图:(10)查询全体学生的学号与姓名;解:SelectSno,Sname;Fromstudent截图:(11)查询全体学生的学号、姓名、所属班级;解:SelectSno,Sname,Sclass;Fromstudent截图:(12)查询全体学生的详细记录;解:Select*;Fromstudent截图:(13)查询全体学生的姓名及其年龄;解:SelectSname,year(date())-year(Sbirthday)asage;Fromstudent截图:(14)查询全体学生的姓名、出生年份;解:SelectSname,Sbirthday;Fromstudent截图:(15)查询所有修过课的学生的学号;解:Selectstudent.Sno;Fromscore,student;Wherescore.Sno=student.Sno截图:(16)查询“信管系0101”班全体学生名单;解:SelectSname;Fromstudent;WhereSclass='信管系0101'截图:(17)查询查询所有年龄在27岁以下的学生姓名及其年龄;解:SelectSname,year(date())-year(Sbirthday)asage;Fromstudent;Whereyear(date())-year(Sbirthday)<=27截图:(18)查询考试成绩有不及格的学生的学号;解:SelectSno;Fromscore;WhereScore<60截图:(19)查询年龄在15至28岁之间的学生姓名、班级和年龄;解:SelectSname,Sclass,year(date())-year(Sbirthday)asage;Fromstudent;Whereyear(date())-year(Sbirthday)>15andyear(date())-year(Sbirthday)<28截图:(20)查询年龄不在15至28岁之间的学生姓名、班级和年龄;解:SelectSname,Sclass,year(date())-year(Sbirthday)asage;Fromstudent;Whereyear(date())-year(Sbirthday)<=15oryear(date())-year(Sbirthday)>=28截图:(21)查询“信管系0101”和“电商系0102”班的学生的姓名和班级信息;解:SelectSname,Sclass;Fromstudent;WhereSclass='信管系0101'orSclass='电商系0102'截图:(22)查询既不是“信管系0101”也不是“电商系0102”班的学生的姓名和班级信息;解:SelectSname,Sclass;Fromstudent;WhereSclass!='信管系0101'andSclass!='电商系0102'截图:(23)查询学号为“011113104”的学生的详细情况;解:Select*;Fromstudent;WhereSno='011113104'截图:(24)查询学号以“0111”打头的学生信息;解:Select*;Fromstudent;Wheresubstr(Sno,1,4)='0111'截图:(25)查询所有姓“张”学生的学号、姓名、性别、年龄;解:SelectSno,Sname,year(date())-year(Sbirthday)asage;Fromstudent;WhereSnamelike'张%'截图:(26)查询名字中第二个字有“海”字的学生的学号、姓名、性别、年龄;解:SelectSno,Sname,year(date())-year(Sbirthday)asage;Fromstudent;Wheresubstr(Sname,3,2)='海'截图:(27)查询所有不姓“刘”学生的姓名;解:SelectSname;Fromstudent;Wheresubstr(Sname,1,2)!='刘'截图:(28)查询课程号以“C”开头的最后两个字母为“05”的课程号和课程名;解:SelectCno,Cname;Fromcourse;WhereCnolike'C%'andsubstr(Cno,3,2)='05'截图:(29)某些学生...