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S(S#,SN,SD,SA)S#,SN,SD,SA·Ö±ð´ú±íѧºÅ£¬Ñ§Ô±ÐÕÃû£¬ËùÊôµ¥Î»£¬Ñ§Ô±ÄêÁä
C(C#,CN)C#,CN·Ö±ð´ú±í¿Î³Ì±àºÅ£¬¿Î³ÌÃû³Æ
SC(S#,C#,G) S#,C#,G·Ö±ð´ú±íѧºÅ£¬ËùÑ¡µÄ¿Î³Ì±àºÅ£¬Ñ§Ï°³É¼¨
(1)ʹÓñê×¼SQLǶÌ×Óï¾ä²éѯѡÐ޿γÌÃû³ÆΪ’Ë°ÊÕ»ù´¡’µÄѧԱѧºÅºÍÐÕÃû?
(2) ʹÓñê×¼SQLǶÌ×Óï¾ä²éѯѡÐ޿γ̱àºÅΪ’C2’µÄѧԱÐÕÃûºÍËùÊôµ¥Î»?
(3) ʹÓñê×¼SQLǶÌ×Óï¾ä²éѯ²»Ñ¡Ð޿γ̱àºÅΪ’C5’µÄѧԱÐÕÃûºÍËùÊôµ¥Î»?
(4) ²éѯѡÐÞÁ˿γ̵ÄѧԱÈËÊý?
(5) ²éѯѡÐ޿γ̳¬¹ý5ÃŵÄѧԱѧºÅºÍËùÊôµ¥Î»?
drop table S;
drop table C;
drop table SC;
create table S
(
S# varchar(10),
SN varchar (25),
SD varchar (25),
SA int
)
create table C
(
C# varchar(10),
CN varchar (25)
)
create table SC
(
S# varchar(10),
C# varchar(10),
G int
Primary Key(S#, C#)
)
insert into S values ('10001','Students1','department1',23)
insert into S values ('10002','Students2','department1',24)
insert into S values ('10003','Students3','department2',25)
insert into S values ('10004','Students4','department2',26)
insert into S values ('10005','Students5','department3',23)
insert into S values ('10006','Students6','department3',24)
insert into S values ('10007','Students7','department3',25)
insert into S values ('10008','Students8','department4',25)
insert into C values ('C1','Êýѧ')
insert into C values ('C2','ÎïÀí')
insert into C values ('C3','»¯Ñ§')
insert into C values ('C4','Ó¢Óï')
insert into C values ('C5','ÖÐÎÄ')
insert into C values ('C6','Ë°ÊÕ»ù´¡')
insert into C values ('C7','´«Ã½')
insert into C values ('C8','ÈÕÓï')
insert into SC values ('10001','C1',67)
insert into SC values ('10001','C2',77)
insert into SC values ('10001','C3',87)
insert into SC values ('10001','C4',97)
insert into SC values ('10001','C5',57)
insert into SC values ('10001','C6',47)
insert into SC values ('10002','C1',62)
insert into SC values ('10002','C2',72)
insert into SC values ('10002','C3',82)
insert into SC values ('10002','C4',92)
insert