rel-ops.txt.txt

来自「ssd7 exercise2 答案」· 文本 代码 · 共 14 行

SELECT Title, Price
FROM BOOK a, PUBLISHER b
WHERE a.PublisherID = b.PublisherID
      AND (b.Pname = '清华大学出版社' OR b.Pname='电子工业出版社'); 


Relational operations:
SELECT, FROM, WHERE, AND, OR
SELECT A FROM B 指从表B中选出属性A，并具备条件S
WHERE连接条件S，S用AND和OR连接。

SELECT Pname
FROM BOOK a, PUBLISHER b
WHERE Title = 'Big C++' AND a.PublisherID = b.PublisherID;