Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Databases Reporting with SQL Aggregate and Numeric Functions Counting Groups

Posted by Derek Morse
Derek Morse
1,776 Points

STUCK AGAIN

SELECT COUNT(genre) FROM books GROUP BY "genre_count";

1 Answer

Adam Dąbrowski
Adam Dąbrowski
1,989 Points
Adam Dąbrowski
Adam Dąbrowski
1,989 Points

First try to understand what you need to deliver, you need to count all books from difrent genres so :

  1. you need to select genre as genre count from table books .
  2. now we know what genres we have , and we need to count all of them,
  3. we have some books that genres dupplicates , i mean one genre can have mmultiple books , so we use group by

now lets write a query:

  1. select genre as genre_count from books
  2. select genre,count(*) as genre_count from books
  3. select genre,count(*) as genre_count from books group by genre;