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Pages per reader

#069BasicJOINGROUP BY5 min

The library wants to give a small prize to its keenest reader. Join loans and books and work out how many pages each reader has borrowed in total (pages added up). Pick reader and the total.

The tables
books
idtitleauthorgenrepagesyear
1The Night GardenMia Lanestory2102015
2Stars for KidsTom Hartscience962020
3Lost at SeaMia Lanestory3402011
4Easy BreadRosa Bellfood1282019
5The Bug BookTom Hartscience642022
6Soup DaysRosa Bellfood1502008
7The Red KiteAnn Colestory1802021
8Rocks and RiversAnn Colescience2202017
8 rows
loans
idbook_idreaderdays
11Leo14
22Nora7
31SamNULL
44Leo21
55NoraNULL
63Ivy10
72Sam5
87Ivy12
8 rows
query.sql
SELECT loans.reader, books.pages
FROM loans
JOIN books ON loans.book_id = books.id
-- your code here: swap books.pages for SUM(books.pages), and GROUP BY loans.reader
;
Ctrl + Enter runs too
Result

Run shows what your query gives. When it looks right, Submit.