cs50 pset7 13.sql - remove kevin from results

问题

UPDATE: I was able to easily and simply solve this problem by changing 2 things:

Add to the end of the code: AND people.name != "Kevin Bacon"
Change nested query to movies.id instead of title.

Thanks to this thread for the answer: CS50 Pset 7 13.sql, I can't solve it, nested sqlite3 database

I'm at the very last step of PSET7 movies (https://cs50.harvard.edu/x/2020/psets/7/movies/) The goal output should be all people that have starred in a movie with Kevin, but Kevin himself should NOT be included.

I have a query that returns a list of all the names of people who starred in movies with Kevin Bacon, but Kevin is there. How can I remove him from the results easily? I've looked into NOT IN, but I can't figure out how to get that to work with nested queries the way I have set this up. So any advice is greatly appreciated.

Here's my code:

SELECT DISTINCT people.name
FROM people
INNER JOIN stars ON stars.person_id = people.id
INNER JOIN movies ON movies.id = stars.movie_id
WHERE movies.title IN (
SELECT DISTINCT movies.title
FROM movies
INNER JOIN stars ON stars.movie_id = movies.id
INNER JOIN people ON people.id = stars.person_id
WHERE people.name = "Kevin Bacon" AND people.birth = "1958");

回答1:

Try

SELECT name 
FROM   people 
WHERE  id IN (SELECT DISTINCT person_id 
              FROM   stars 
              WHERE  movie_id IN (SELECT movie_id 
                                  FROM   stars 
                                         INNER JOIN people 
                                                 ON stars.person_id = people.id 
                                  WHERE  people.name = "kevin bacon" 
                                         AND people.birth = 1958)) 
       AND NOT ( name = "kevin bacon" 
                 AND birth = 1958 );

Explanation-

First SELECT all movie_ids where "kevin bacon" (the one who was born in 1958) has starred
Now SELECT all person_ids who've starred in the aforementioned movies
Now SELECT the names of all these people
Finally, exclude only "kevin bacon" (the one who was born in 1958) from this result

来源：https://stackoverflow.com/questions/62975869/cs50-pset7-13-sql-remove-kevin-from-results

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