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Databases

Posted by Allambi Care
Allambi Care
2,393 Points

SQL Query Issue

Having trouble with query to count all unique genres using count and distinct. Query used does not give desired result.

I am not sure what I am missing with the attached code to get the correct result.

SELECT count(*) AS total_genres FROM ( SELECT DISTINCT(genre) FROM books)

1 Answer

jcorum
jcorum
71,830 Points

Callan, you didn't give a link, so we're left guessing. But if it is this challenge:

https://teamtreehouse.com/library/reporting-with-sql/aggregate-and-numeric-functions/counting-groups

Then you need two different SQL statements, one for Task 1 and one for Task 2:

SELECT genre, COUNT(*) AS genre_count FROM books GROUP BY genre;

SELECT COUNT(DISTINCT genre) AS total_genres FROM books;
Allambi Care
Allambi Care
2,393 Points

Sorry about the lack of link. Cheers, I see you include the distinct(genre) within the count rather than in the from.