query: #title: Duplicate identifiers differing only in case
  # Complex constraint from [[Property talk:P2002]]
  # These items have the same Twitter ID twice, but with different casing. N.B. Please do <em>not</em> fix automatically by removing entries without checking them first as one value may have key qualifiers (follower count, verification, sources, etc)!
  SELECT DISTINCT ?item ?twitter1 ?twitter2 WHERE
  {
    ?item wdt:P2002 ?twitter1 . ?item wdt:P2002 ?twitter2 .
    FILTER(?twitter1 > ?twitter2) .
    # item has two values for twitter account
    FILTER(LCASE(?twitter1) = LCASE(?twitter2)) .
    # but they are the same case-insensitive text
  }