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Databases

HIDAYATULLAH ARGHANDABI
HIDAYATULLAH ARGHANDABI
21,058 Points

Is there a mistake in my code > SELECT DISTINCT genre, count(*) as genre_count FROM books GROUP BY genre;

SELECT DISTINCT genre, count(*) as genre_count FROM books GROUP BY genre;

can some one help

Matthew Lang
Matthew Lang
13,483 Points

Your SQL looks perfectly valid, if that's what you're asking. I can't imagine you're asking how to solve the question though, since you never actually included the question at hand.

3 Answers

Steven Parker
Steven Parker
231,236 Points

Now that you have shown the actual task, I can give you more specific hints:

  • the challenge asks only for the count, so you won't need to select "genre"
  • you also won't need the ""GROUP BY`" clause
  • the challenge asks you "to count all the unique genres", so you'll need to specify the field to count
  • you will still use the word "DISTINCT", but as part of the count argument
HIDAYATULLAH ARGHANDABI
HIDAYATULLAH ARGHANDABI
21,058 Points

SELECT distinct genre, count(*) as total_genres FROM books;

is this what u mean sir

Steven Parker
Steven Parker
231,236 Points

As I hinted, you don't need to select "genre" as a separate column, but you do need to include it (along with "DISTINCT") as the argument to "COUNT":

SELECT COUNT(DISTINCT genre) AS total_genres FROM books;
Chandlerj Jones
Chandlerj Jones
18,378 Points

When answering this, the submission requires you to include "GROUP BY". When I attempted my solution using your suggestions I received: "Bummer: You're missing the GROUP BY keywords."

Steven Parker
Steven Parker
231,236 Points

You may be confusing this with a different exercise. You don't need grouping to get a count of all the genres, but you would to get the count of books in each genre.

HIDAYATULLAH ARGHANDABI
HIDAYATULLAH ARGHANDABI
21,058 Points

In the library database there's a books table. There are id, title, author, genre and first_published columns. Write a query to count all the unique genres in the books table. Alias it as total_genres. Type in your command below. Get Help

SELECT distinct genre, count(*) as total_genres FROM books group by genre;