SQL_實驗1.3 清華大學出版社

/*1.*/insertinto studentsvalues('70045678','LiMing','LX@cdemg.com',1992);/*2.*/create table choices_result(cid char(10),students smallint,avgscore smallint);insert into choices_resultselect cid, count(sid), avg(score)from choicesgroup by cid;/*3*/update studentsset grade = '2002'where sname = 'LiMing';

/*4.*/update teachersset salary=salary+500;/*5.*/update choicesset score=score+5where choices.no=(select choices.nofrom choices,courses,studentswhere courses.cid=choices.cid and students.sid = choices.sidand courses.cname = 'c' and students.sname = 'zapyv');/*6.*/delete studentswhere sname = 'LiMing';/*7.*/deletefrom choiceswhere 'java' = (select cnamefrom courseswhere courses.cid = choices.cid);/*8.*/deletefrom choiceswhere choices.cid in(select courses.cidfrom courseswhere courses.hour < 48);delete courseswhere hour < 48;