Containers - Quarry

SQL

SET @c = 'American_screenwriters';
SELECT
  pg1.page_title,
  subs.cl_to
FROM
  page AS pg1
  JOIN categorylinks AS cl1 ON cl1.cl_from = pg1.page_id
  JOIN (
    SELECT
      cl2.cl_from,
      cl2.cl_to
    FROM
      categorylinks AS cl2
    WHERE
      cl2.cl_to IN (
        SELECT
          page_title
        FROM
          page pg3
          JOIN categorylinks AS cl3 ON pg3.page_id = cl3.cl_from
        WHERE
          cl3.cl_to = @c
          AND cl3.cl_type = 'subcat'
      )
  ) AS subs ON subs.cl_from = cl1.cl_from
WHERE
  cl1.cl_to = @c
  AND cl1.cl_type = 'page'
  AND page_namespace = 0
LIMIT 1;

SELECT *
FROM categorylinks cl
WHERE cl_to = @c
AND cl_type = 'subcat'
LIMIT 100;
SQL

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