Odd and Even Page Counts per Shelving Day

Problem

A library logs every book returned to the stacks in the table `returns_log`. Each row has a `return_id`, the book's `page_count` (a whole number), and the `shelved_on` date the book was reshelved.

For each shelving day, report two sums: `odd_pages` — the total of all `page_count` values that are odd — and `even_pages` — the total of all `page_count` values that are even. A day that has no odd (or no even) books should still report that sum as 0 rather than NULL. Return one row per `shelved_on` date and order the result by `shelved_on`.

Tables

Example rows — the live problem includes the full dataset.

Expected output

Your answer should return 3 rows with the columns shelved_on, odd_pages, even_pages.

Starter code (SQL)

SELECT *
FROM returns_log;

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