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Databases Reporting with SQL Aggregate and Numeric Functions Counting Groups

Posted by Kawaljeet Singh
Kawaljeet Singh
3,820 Points

GROUP BY

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.

My Answer- select COLUMN(DISTINCT genre) AS "total_genre" from books GROUP BY genre PLease highligh my mistake and explain the answer. Thank you

1 Answer

Steven Parker
Steven Parker
229,644 Points
Steven Parker
Steven Parker
229,644 Points

The challenge error message contained a hint: "Bummer: You're missing the COUNT() function."

That's one of three issues:

  • you have "COLUMN" instead of "COUNT"
  • you have "total_genre" (singular) but the instructions asked for "total_genres"
  • you don't need GROUP BY for this
Kawaljeet Singh
Kawaljeet Singh
3,820 Points

Hi I still tried but its not proper answer. select COUNT(DISTINCT genre) AS total_genres from books GROUP BY genre;

Steven Parker
Steven Parker
229,644 Points
Steven Parker
Steven Parker
229,644 Points

Kawaljeet Singh — Ooops, I forgot there was a third issue. I updated my answer.
Did you get it now?