SQL

使用SQL语句查出哪些人即会玩basketball又会玩badminton，找出这样的name-hobby组合

create table test (NAME varchar(20) not null, HOBBY varchar(20) not null);    
insert into test values('Adam','basketball');  
insert into test values('Bill','basketball');  
insert into test values('Bill','football');  
insert into test values('Cyper','basketball');  
insert into test values('Cyper','badminton');  
insert into test values('David','basketball');  
insert into test values('David','badminton');  
insert into test values('David','table tennis');
select * from test t;
--(1)with
WITH  
NAME_MATCHES AS  
(SELECT NAME  
  FROM TEST  
     WHERE HOBBY IN ('basketball', 'badminton')  
    GROUP BY NAME  
     HAVING COUNT(NAME) = 2)  
SELECT T.*  
 FROM TEST T, NAME_MATCHES NM  
 WHERE T.NAME = NM.NAME;
--(2)exists and exists
SELECT *  
  FROM TEST T1  
  WHERE EXISTS (SELECT *  
          FROM TEST T2  
          WHERE T2.NAME = T1.NAME AND HOBBY = 'basketball')  
    AND EXISTS (SELECT *  
          FROM TEST T3  
          WHERE T3.NAME = T1.NAME AND HOBBY = 'badminton');  
--(3)self join
SELECT T1.*  
  FROM TEST T1, TEST T2, TEST T3  
  WHERE T1.NAME = T2.NAME AND T1.NAME = T3.NAME AND T2.HOBBY = 'basketball'  
    AND T3.HOBBY = 'badminton';