SQL / MYSQL：一個查詢中的兩個語句

Question

film_actor ，像這樣：

╔═════════╦══════╗
║ film_id ║ Task ║
╠═════════╬══════╣
║    1    ║ 162  ║
║    1    ║ 15   ║
║    1    ║ 20   ║
║    2    ║ 162  ║
║    2    ║ 12   ║
╚═════════╩══════╝

比以下查詢：

SELECT film_id
FROM film_actor
WHERE actor_id LIKE '162'

結果：

1
2

下一個查詢：

SELECT DISTINCT actor_id
FROM film_actor
WHERE film_id LIKE 'results from the query above'

結果應該是這樣的：

15
20
12

我怎樣才能把這兩個查詢放在一起？ 第一個的結果不應該被顯示，它只是第二次和最終查詢所需要的。

Answer 1

使用IN運算符：

SELECT DISTINCT actor_id
FROM film_actor
WHERE film_id in(SELECT film_id
                 FROM film_actor
                 WHERE actor_id LIKE '162')

或者使用JOIN ：

SELECT DISTINCT f2.actor_id
FROM film_actor f1
JOIN film_actor f2 ON f1.film_id = f2.film_id
WHERE f1.actor_id LIKE '162'

Answer 2

SELECT DISTINCT actor_id
FROM film_actor
WHERE film_id IN
(
    SELECT film_id
    FROM film_actor
    WHERE actor_id LIKE '162'
)

Answer 3

就是這樣

SELECT DISTINCT actor_id
FROM film_actor
WHERE film_id in (
  SELECT film_id
  FROM film_actor
  WHERE actor_id LIKE '162'
);

Answer 4

你要找的是subquery 。 你的應該是這樣的：

SELECT DISTINCT actor_id FROM film_actor WHERE film_id in
(SELECT film_id FROM film_actor WHERE actor_id LIKE '162)