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cs50 / check50

This is check50, a command-line program with which you can check the correctness of your programs.
GNU General Public License v3.0
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Possible bug in check50 for movies problem set in 4th exercise. #346

Closed AnderGI closed 3 months ago

AnderGI commented 3 months ago

Exercise description:

In 4.sql, write a SQL query to determine the number of movies with an IMDb rating of 10.0.

Query

SELECT COUNT(id) FROM movies WHERE id = ( SELECT movie_id FROM ratings WHERE rating = 10.0 );

Output in the check50

SELECT COUNT(id) FROM movies WHERE id = ( SELECT movie_id FROM ratings WHERE rating = 10.0 );

Result

Executing 4.sql results in a table with 1 column and 1 row.

Isn't there an inconsistency issue in that test case?

AnderGI commented 3 months ago

SELECT COUNT(id) FROM movies WHERE id IN ( SELECT DISTINCT movie_id FROM ratings WHERE rating = 10.0 ); IN for multiple rows DISTINCT for avoiding duplicates