The total file size under the Library Back-Up Project on Wikimedia Commons

SQL

SELECT
  IFNULL(cl.cl_to, 'Total') AS Category,
  COUNT(*) AS LikeCount,
  SUM(CAST(i.img_size AS SIGNED) / POWER(10, 12)) AS TotalFileSizeTB
FROM
  page AS p
  JOIN categorylinks AS cl ON p.page_id = cl.cl_from
  JOIN image AS i ON p.page_title = i.img_name
WHERE
  cl.cl_to IN (
    SELECT page_title
    FROM categorylinks
    JOIN page ON page_id = cl_from
    WHERE (cl_to = 'Library_back_up_project' OR cl_to = 'Books_from_the_National_Library_of_China')
    AND page_namespace = 14
  )
  AND p.page_namespace = 6
GROUP BY cl.cl_to WITH ROLLUP;

SQL

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