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Databases Reporting with SQL Aggregate and Numeric Functions Counting Groups

Kevin May
Kevin May
1,435 Points
Posted by Kevin May
Kevin May
1,435 Points

When asked "Write a query to count all the unique genres in the books table. Alias it as total_genres." get wrong count?

I write "SELECT DISTINCT COUNT(genre) AS total_genres FROM books;" but the system states I did not get the correct count. I have tried writing SELECT DISTINCT genre, COUNT(*) FROM books GROUP BY genre; and several variations, but still nothing is working? Am I missing something?

2 Answers

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,967 Points

Here's a link on count distinct. What you are looking for:

SELECT COUNT (DISTINCT genre) AS total_genres FROM books
Kevin May
Kevin May
1,435 Points
Kevin May
Kevin May
1,435 Points

Thanks, that worked! Didn't realize I needed to add DISTINCT within the COUNT.