SQL：获取父级子项类型= 1且子类型= 2的子项

Question

我在SQL（MySQL环境）中有疑问。 我有两张桌子：

Airports
--------------------
id    type   city_id
1     2      1
2     3      1
3     4      2


City
----------
id    name
1     Paris
2     Lyon

我想要机场类型为2和3的城市。

我试过了：

SELECT *
FROM city c INNER JOIN airports a ON a.city_id = c.id
WHERE a.type = 1 AND a.type = 2

但它不起作用。

有任何想法吗 ？

Answer 1

如果你在记录巴黎之后有两种不同的类型（1和2），试试这个：

SELECT c.*
FROM city c INNER JOIN 
     airports a ON a.city_id = c.id
WHERE a.type IN (2,3)
HAVING COUNT(DISTINCT a.type)>1

结果：

ID  NAME
1   Paris

在SQL Fiddle中查看结果。

更详细一点：

SELECT c.id as CID,a.Id as AID,type,city_id,name
FROM city c INNER JOIN
     airports a ON a.city_id=c.id LEFT JOIN
(SELECT c.id
 FROM city c INNER JOIN 
      airports a ON a.city_id = c.id
 WHERE a.type IN (2,3)
 HAVING COUNT(DISTINCT a.type)>1) T ON T.id=c.id
WHERE T.id IS NOT NULL

结果：

CID  AID    TYPE    CITY_ID  NAME
1    1      2       1        Paris
1    2      3       1        Paris

小提琴示例 。

Answer 2

如果您需要存在类型1和2机场的城市，请尝试使用此查询：

SELECT * FROM CITY
JOIN
  (
     SELECT CITY_ID FROM Airports WHERE type in (1,2)
     GROUP BY CITY_ID
     HAVING COUNT(DISTINCT type) =2
   ) as A
  ON City.ID=a.City_id

Answer 3

您可以使用子查询

 SELECT * FROM (
   SELECT *, GROUP_CONCAT(a.type) as tp
   FROM city c INNER JOIN airports a ON a.city_id = c.id
   WHERE a.type IN (1,2)
) tmp WHERE tp = "1,2";

在这里，您可以使用所需的值替换1,2（在子查询中）

 SELECT * FROM (
   SELECT c.id, c.name, GROUP_CONCAT(a.type) as tp
   FROM city c JOIN airports a ON a.city_id = c.id
   WHERE a.type IN (2,3)
) tmp WHERE tp = "2,3";

上面的一个也返回正确的数据

Answer 4

你能试试吗？

SELECT *
FROM city c jINNER JOIN (
    SELECT DISTINCT city_id
    FROM airports t1 INNER JOIN airports t2
        ON t1.city_id = t2.city_id
    WHERE t1.type = 1 AND t2.type = 2
) a ON a.city_id = c.id

Answer 5

select c.name from city c where exists
(select * from airport a where a.city_id=c.id and exists
(select * from airport a1 where a1.type=2 and a1.city_id=a.city_id and 
exists(select * from airport a2 where a2.type=3 and a2.city_id=a1.city_id)))

检查此示例输出SQL FIDDLE

Answer 6

您可以使用子查询。试试这个

Select Id,Name from City 
where Id in(Select distinct CityId from Airports where Type in(2,3))