Userspace links in articles

SQL

-- See [[Special:Diff/904016069]]
SELECT *
FROM (
SELECT
  pl_from,
  -- pl_from_namespace does not appear to be consistently reliable;
  -- it might be better to select from the page table and join the pagelinks table to it.
  CASE
    -- This fails on pages missing from the page table (presumably because they were deleted).
    WHEN pl_from_namespace != page_namespace THEN CONCAT(pl_from_namespace, ' vs. ', page_namespace)
    ELSE pl_from_namespace
  END AS 'NS',
  page_title,
  pl_namespace AS 'L NS',
  GROUP_CONCAT(pl_title SEPARATOR ' ') AS 'L titles',
  COUNT(pl_title) AS num_L,
  CASE
    WHEN MAX(CASE WHEN pl_title LIKE '%/sandbox' THEN 1 END) = 1 THEN '(SB)'
    ELSE ''
  END AS SB,
  CASE
    WHEN EXISTS(
      SELECT 1
      FROM templatelinks
      WHERE
        tl_from = pl_from
        AND tl_title = 'Under_construction'
    ) THEN '(C)'
    ELSE ''
  END AS C,
  CASE
    WHEN EXISTS(
      SELECT 1
      FROM category_links
      WHERE
        cl_from = pl_from
        AND cl_title = 'Pages_using_Under_construction_with_the_placedby_parameter'
    ) THEN '(PB)'
    ELSE ''
  END AS C_PB,
  CASE
    WHEN EXISTS(
      SELECT 1
      FROM templatelinks
      WHERE
        tl_from = pl_from
        AND (tl_title = 'In use' OR tl_title = 'GOCEinuse')
    ) THEN '(IU)'
    ELSE ''
  END AS IU,
  CASE 
    WHEN EXISTS(
      SELECT 1
      FROM templatelinks
      WHERE
        tl_from = pl_from
        AND tl_title = 'Db-r2'
    ) THEN '(R2)'
    ELSE ''
  END AS R2,
  CASE
    WHEN EXISTS(
      SELECT 1
      FROM templatelinks
      WHERE
        tl_from = pl_from
        AND tl_title = 'Copyvio-revdel'
    ) THEN '(RD1)'
    ELSE ''
  END AS RD1,
  CASE
    WHEN EXISTS(
      SELECT 1
      FROM templatelinks
      WHERE
        tl_from = pl_from
        AND tl_title = 'Wikipedia_person_user_link'
    ) THEN '(WP)'
    ELSE ''
  END AS WP
FROM pagelinks
LEFT JOIN page ON page_id = pl_from
WHERE
  pl_from_namespace = 0
  AND pl_namespace = 2
  -- AND pl_namespace != 0
GROUP BY pl_from -- An unfortunate necessity to avoid excessive templatelinks rows
ORDER BY SB, page_title
) AS t1
WHERE
  (C = '' OR num_L != 1)
  AND (R2 = '' OR num_L != 1)
  AND (RD1 = '' OR num_L != 1)
  AND (WP = '' OR num_L != 1)
  AND (C_PB = '' OR num_L > 2)
SQL

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