学生表sid,sname,成绩表cid,cname,学生成绩表sid,cid,cscore,要

--1、建表SQL: --学生表： -- Createtable createtable STUDENT ( SID NUMBERnotnull, SNAME NVARCHAR2(40) ) tablespace CABLESCD pctfree10 initrans1 maxtrans255 storage ( initial64 minextents1 maxextentsunlimited ); --成绩表 -- Createtable creat

--1、建表SQL:

--学生表：

-- Createtable

createtable STUDENT

(

SID NUMBERnotnull,

SNAME NVARCHAR2(40)

)

tablespace CABLESCD

pctfree10

initrans1

maxtrans255

storage

(

initial64

minextents1

maxextentsunlimited

);

--成绩表

-- Createtable

createtable SCORE

(

CID NUMBERnotnull,

CNAME NVARCHAR2(40) notnull

)

tablespace CABLESCD

pctfree10

initrans1

maxtrans255

storage

(

initial64

minextents1

maxextentsunlimited

);

--学生成绩表

-- Createtable

createtableSTUDENGSCORE

(

SID NUMBERnotnull,

CID NUMBERnotnull,

CSCORE NUMBER(4,2)

)

tablespace CABLESCD

pctfree10

initrans1

maxtrans255

storage

(

initial64

minextents1

maxextentsunlimited

);

--2、插入SQL语句：

insert into student

(sid, sname)

values

(001,'ZHAOHY');

insert into student

(sid, sname)

values

(002, 'ZHANGQL');

insert into student

(sid, sname)

values

(003, 'ZHAOHB');

insert into score

(cid, cname)

values

(100, '数电');

insert into score

(cid, cname)

values

(200, '模电');

insert into score

(cid, cname)

values

(300, '英语');

insert into score

(cid, cname)

values

(400, '政治');

select * from score

(001, 100, '60');

insert into studengscore

(sid, cid, cscore)

values

(002, 100, '70');

insert into studengscore

(sid, cid, cscore)

values

(003, 100, '80');

insert into studengscore

(sid, cid, cscore)

values

(003, 200, '90');

insert into studengscore

(sid, cid, cscore)

values

(003, 300, '99');

insert into studengscore

(sid, cid, cscore)

values

(003, 400, '98');

select * from studengscore

--3、查询SQL

select * fromstudengscore;

select * from student;

select * from score;

select cnamefrom score where cid =(select cid fromstudengscore wherecscore=(

selectmax(cscore) fromstudengscore where sid=3 ));