[mysql] mysql count group by having

I have this table:

Movies (ID, Genre)

A movie can have multiple genres, so an ID is not specific to a genre, it is a many to many relationship. I want a query to find the total number of movies which have at exactly 4 genres. The current query I have is

  SELECT COUNT(*) 
    FROM Movies 
GROUP BY ID 
  HAVING COUNT(Genre) = 4

However, this returns me a list of 4's instead of the total sum. How do I get the sum total sum instead of a list of count(*)?

This question is related to mysql sql group-by aggregate-functions

The answer is


SELECT COUNT(*) 
FROM   (SELECT COUNT(*) 
        FROM   movies 
        GROUP  BY id 
        HAVING COUNT(genre) = 4) t

What about:

SELECT COUNT(*) FROM (SELECT ID FROM Movies GROUP BY ID HAVING COUNT(Genre)=4) a

Maybe

SELECT count(*) FROM (
    SELECT COUNT(*) FROM Movies GROUP BY ID HAVING count(Genre) = 4
) AS the_count_total

although that would not be the sum of all the movies, just how many have 4 genre's.

So maybe you want

SELECT sum(
    SELECT COUNT(*) FROM Movies GROUP BY ID having Count(Genre) = 4
) as the_sum_total

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