SQL：获取父级子项类型= 1且子类型= 2的子项

Question

I have question in SQL (MySQL environment). I have two tables:

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


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

I want cities with airports whose type is 2 and 3.

I have try:

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

But it does not work.

Any ideas ?

Answer 1

If you are after the record paris which has two different types(1 and 2), try this:

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

Result:

ID  NAME
1   Paris

See result in SQL Fiddle .

To be more detailed:

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

Result:

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

Fiddle Example .

Answer 2

If you need cities where type 1 and 2 airports exist both then try to use this query:

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

You can use a sub-query

 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";

And here you replace 1,2 (in the sub-query also) with the values you require

 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";

the above one returns correct data also

Answer 4

Could you try this?

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)))

Check this for sample output SQL FIDDLE

Answer 6

You can use subquery for this.. Try this

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