18. Top film category

easy

Instruction
  • Write a query to return the film category id with the most films, as well as the number films in that category.

Table: film_category

A film can only belong to one category


  col_name   | col_type
-------------+--------------------------
 film_id     | smallint
 category_id | smallint

Sample results


category_id | film_cnt
------------+----------
          1 |       2

Solution postgres

SELECT 
    category_id,
    COUNT(*) film_cnt
FROM film_category
GROUP BY category_id
ORDER BY film_cnt DESC
LIMIT 1;
    

Explanation

This query is selecting the category_id column and counting the number of films in each category by grouping the results by category_id using the film_category table. The results will be ordered in descending order by the film count (film_cnt) and only the top result will be returned due to the LIMIT 1 clause. This query is useful for finding the category with the most films in the database.

Last Submission postgres

Expected results



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