SELECT CONCAT('Template:', p1.page_title), p2.page_is_redirect AS 'exists as redirect'

FROM page p1

LEFT JOIN page AS p2 ON p2.page_namespace = 0 AND p2.page_title = SUBSTRING(p1.page_title, LENGTH('Editnotices/Page/') + 1)

WHERE p1.page_namespace = 10  -- template

  AND p1.page_title LIKE 'Editnotices/Page/%'

  -- exclude editnotices with a colon since they are not in mainspace. for example, exclude Editnotice/Page/Category:Test

  AND p1.page_title NOT LIKE '%:%'

  AND (p2.page_is_redirect IS NULL -- doesn't exist

       OR p2.page_is_redirect = 1) -- exists as redirect

  AND p1.page_is_redirect = 0

ORDER BY p1.page_title ASC;