This query is designed to provide insights into the sales performance of authors in the year 2022. Specifically, it lists the top 5 authors by revenue generated from their book sales within that year.
Components:
authors: Contains details about authors, including their ID and name. books: Contains details about books, including their associated author, publication year, and price. sales: Contains records of book sales, including the book ID, sale date, and quantity sold.
The query begins by selecting from the authors table, aliased as 'a'. It then joins with the books table (aliased as 'b') on the author_id to correlate authors with their books. Finally, it joins with the sales table (aliased as 's') on the book_id to correlate books with their sales records.
The WHERE clause filters the results to only consider sales records from the year 2022.
The SUM function calculates the total revenue for each author. This is done by multiplying the price of a book (b.price) with the quantity sold (s.quantity_sold). Results are grouped by author_id and name ensuring that revenues are aggregated per author.
Results are ordered in descending order by total_revenue, ensuring the top-performing authors are listed first. The LIMIT 5 clause restricts the output to only show the top 5 authors by revenue.
The resulting output of this query provides a list of the top 5 authors who generated the highest revenue from their book sales in 2022. Each record in the result consists of the author_id, author_name, and their respective total_revenue.