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Databases

Philip Rurka
Philip Rurka
8,633 Points
Posted by Philip Rurka
Philip Rurka
8,633 Points

A question with SQL involving one of the code challenges.

Hello. The question I am faced with is this:

In the library database there's a books table. There are id, title, author, genre and first_published columns. Count all the books in each genre. Include the genre column first and the genre_count as the second column of information.

My answer is this :

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

I am getting an error saying "Your query didn't perform the correct count." I can't figure out what is wrong.

Philip Gales
Philip Gales
15,193 Points

Can you link the the challenge?

3 Answers

Unsubscribed User
Unsubscribed User
3,913 Points
Unsubscribed User
Unsubscribed User
3,913 Points

Your answer should be counting the number of rows returned for each genre. Your query should read:

SELECT GENRE, COUNT(*) AS genre_count FROM BOOKS GROUP BY GENRE;

BRYANT GOLD
BRYANT GOLD
5,475 Points
BRYANT GOLD
BRYANT GOLD
5,475 Points

Select genre, count(genre) as [genre_count] From books Group by genre;

Jonathan Grieve
MOD
Jonathan Grieve
Treehouse Moderator 91,253 Points
Jonathan Grieve
Jonathan Grieve
Treehouse Moderator 91,253 Points 
SELECT COUNT(genre) AS genre_count FROM books GROUP BY genre;

Try removing the genre column, since you're retrieving the column via your COUNT() function. :-)