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Databases

david hollaway
david hollaway
15,771 Points
Posted by david hollaway
david hollaway
15,771 Points

SQL Count functio()

I'm getting the following error in the Report with SQL (https://teamtreehouse.com/library/reporting-with-sql/aggregate-and-numeric-functions/counting-groups):

Bummer! Your query didn't perform the correct count.

Here is the question:

""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.

Type in your command below.

Here is my code: SELECT genre, COUNT(genre) AS genre_count FROM books GROUP BY genre; SELECT genre, COUNT(genre) AS genre_count FROM books WHERE genre IS NOT NULL GROUP BY genre;

1 Answer

eck
eck
43,038 Points

You are pretty close with the first query you posted. Instead of COUNT(genre) you want to count with a field that is not nullable.

You want something like:

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

You could also do COUNT(id) to get the same result.