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Databases

Posted by Babatunde Obidare
Babatunde Obidare
Courses Plus Student 10,514 Points

Your query didn't perform the correct count? Why?

Why is the query not performing the correct count?

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

1 Answer

Marcia Haledjian
Marcia Haledjian
7,562 Points
Marcia Haledjian
Marcia Haledjian
7,562 Points

You do not use GROUP BY with DISTINCT.

SELECT COUNT(DISTINCT <column>) FROM <table>;

To count aggregated rows with common values use the GROUP BY keywords: SELECT COUNT(<column>) FROM <table> GROUP BY <column with common value>;