将INTERSECT语句翻译为MySQL

Question

我使用INTERSECT进行了以下查询，我无法弄清楚如何使用INNER JOIN将其翻译为MySQL。

SELECT DISTINCT Title, Variable FROM Table WHERE Location='Location1' AND Date='Date1' 
INTERSECT 
SELECT DISTINCT Title, Variable FROM Table WHERE Location='Location2' AND Date='Date2' 
INTERSECT 
SELECT DISTINCT Title, Variable FROM Table WHERE Location='Location3' AND Date='Date3' 

任何人都可以帮我一把吗？

Answer 1

SELECT t1.Title, t1.Variable 
FROM Table t1 
JOIN Table t2 USING (Title, Variable) 
JOIN Table t3 USING (Title, Variable) 
WHERE (t1.Location, t1.Date) = ('Location1', 'Date1') 
    AND (t2.Location, t2.Date) = ('Location2', 'Date2') 
    AND (t3.Location, t3.Date) = ('Location3', 'Date3'); 

您可能需要使用SELECT DISTINCT但我不能说，因为我不知道你的表结构，唯一约束等

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重新您的神秘评论：我尝试以下剧本在我的测试数据库：

DROP TABLE IF EXISTS MyTable; 
CREATE TABLE MyTable (
id  SERIAL PRIMARY KEY, 
title VARCHAR(20) NOT NULL, 
variable VARCHAR(20) NOT NULL, 
location VARCHAR(20) NOT NULL, 
date  DATE NOT NULL 
); 

INSERT INTO MyTable VALUES 
(DEFAULT, 'A Tale of Two Cities', 'variable', 'America', '2010-01-01'), 
(DEFAULT, 'A Tale of Two Cities', 'variable', 'England', '2010-02-01'), 
(DEFAULT, 'A Tale of Two Cities', 'variable', 'France', '2010-03-01'); 

SELECT t1.Title, t1.Variable 
FROM MyTable t1 
JOIN MyTable t2 USING (Title, Variable) 
JOIN MyTable t3 USING (Title, Variable) 
WHERE (t1.Location, t1.Date) = ('America', '2010-01-01') 
    AND (t2.Location, t2.Date) = ('England', '2010-02-01') 
    AND (t3.Location, t3.Date) = ('France', '2010-03-01'); 

输出是这样的：

+----------------------+----------+ 
| Title    | Variable | 
+----------------------+----------+ 
| A Tale of Two Cities | variable | 
+----------------------+----------+