MySQL 交集 實現方法

1

MySQL中如何?以下SQL查詢
(SELECT S.Name
FROM STUDENT S, TRANSCRIPT T
WHERE S.StudId = T.StudId AND T.CrsCode = 'CS305')
INTERSECT
(SELECT S.Name
FROM STUDENT S, TRANSCRIPT T
WHERE S.StudId = T.StudId AND T.CrsCode = 'CS315')

請各位不吝賜教，小弟先謝過~

解：

取交集

select a.* from
(
SELECT S.Name
FROM STUDENT S, TRANSCRIPT T
WHERE S.StudId = T.StudId AND T.CrsCode = 'CS305'
) as a
cross join
(
SELECT S.Name
FROM STUDENT S, TRANSCRIPT T
WHERE S.StudId = T.StudId AND T.CrsCode = 'CS315'
) as b on a.Name = b.Name;

2.

 

SELECT * FROM (
SELECT DISTINCT col1 FROM t1 WHERE...
UNION ALL
SELECT DISTINCT col1 FROM t1 WHERE...
) AS tbl
GROUP BY tbl.col1 HAVING COUNT(*) = 2
3.

交集：

SELECT * FROM table1 AS a JOIN table2 AS b ON a.name =b.name

舉例：

表a:
FieldA
001
002
003

表b:
FieldA
001
002
003
004

請教如何才能得出以下結果集，即表A, B行交集
FieldA
001
002
003

答案：select a.FieldA from a inner join b on a.FieldA=b.FieldA

差集：

NOT IN 表示差集
SELECT * FROM table1 WHERE name NOT IN (SELECT name FROM table2)