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Databases Reporting with SQL Aggregate and Numeric Functions Counting Groups

Posted by Caleb Newell
Caleb Newell
12,562 Points

Write a query to count all the unique genres in the books table. Alias it as total_genres.

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.

When i put in the query i wrote, it sais, "Your'e query did not preform the correct count."

help is much appreciated :)

Steven Parker
Steven Parker
229,785 Points
Steven Parker
Steven Parker
229,785 Points

Please show the query you were entering.

Caleb Newell
Caleb Newell
12,562 Points

Sorry, I don' know why my code did not show up earlier. 

SELECT DISTINCT genre, COUNT(*) AS toatal_genres FROM books;

1 Answer

Steven Parker
Steven Parker
229,785 Points
Steven Parker
Steven Parker
229,785 Points

There seems to be a few issues:

  • the instructions only ask for a total count, not a list of genres
  • the "count" needs to be distinct, not the select
  • the alias is set to "toatal_genres" (with an extra "a") instead of "total_genres"
SELECT COUNT(DISTINCT genre) AS total_genres FROM books;