SQL _ experiment 1.3 Tsinghua University Press

/* 1. */insertinto studentsvalues ('123456', 'liming', 'lx @ cdemg.com ', 70045678);/* 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 = '000000' where sname = 'liming ';

/* 4. */update teachersset salary = salary + 500;/* 5. */update choicesset score = score + 5 where 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;