Sqlite 如何从嵌套select中指定至少有x个值的where子句

假设我有这些表：

人

最喜欢的食物

我想得到一份名单，列出至少喜欢第五个人喜欢的食物的人的名字。如下所示：

SELECT p.name FROM person p
LEFT JOIN favourite_food ff ON ff.personid = p.id
WHERE ff.food = (SELECT food FROM favourite_food WHERE personid = 5)
AND ff.personid <> 5;

---

但我不知道如何指定“至少”部分。我必须创建一个临时表吗？

SQL基本上是与集合一起工作的，因此它通常有助于严格按照集合论重新构造问题

至少可以这样重新制定： 如果我们只看第五个人最喜欢的食物，哪些人的最喜欢食物的数量与第五个人相同

SELECT name
FROM person
WHERE id IN (SELECT personid
             FROM favourite_food
             WHERE food IN (SELECT food
                            FROM favourite_food
                            WHERE personid = 5)
             GROUP BY personid
             HAVING COUNT(food) = (SELECT COUNT(food)
                                   FROM favourite_food
                                   WHERE personid = 5)
            )

或者，使用以下重新表述： 我们不想要那些不喜欢第五个人喜欢的食物的人。 因此，找出不存在第5人喜欢但该人不喜欢的食物的所有人：

SELECT name
FROM person
WHERE NOT EXISTS (SELECT 1
                  FROM favourite_food AS person5_food
                  WHERE personid = 5
                    AND NOT EXISTS (SELECT 1
                                    FROM favourite_food
                                    WHERE personid = person.id
                                      AND food = person5_food.food)
                 )

实际上，SQL是基于的，您需要的操作称为除法

SELECT name
FROM person
WHERE id IN (SELECT personid
             FROM favourite_food
             WHERE food IN (SELECT food
                            FROM favourite_food
                            WHERE personid = 5)
             GROUP BY personid
             HAVING COUNT(food) = (SELECT COUNT(food)
                                   FROM favourite_food
                                   WHERE personid = 5)
            )

SELECT name
FROM person
WHERE NOT EXISTS (SELECT 1
                  FROM favourite_food AS person5_food
                  WHERE personid = 5
                    AND NOT EXISTS (SELECT 1
                                    FROM favourite_food
                                    WHERE personid = person.id
                                      AND food = person5_food.food)
                 )