{12} Active Tickets by Owner

AmbiguousColumn: column reference "description" is ambiguous
LINE 6:    changetime AS _changetime, description AS _description,
                                      ^

SELECT COUNT(*) FROM (

SELECT p.value AS __color__,
   owner AS __group__,
   id AS ticket, summary, component, milestone, t.type AS type, time AS created,
   changetime AS _changetime, description AS _description,
   reporter AS _reporter
  FROM ticket t
  LEFT JOIN enum p ON p.name = t.priority AND p.type = 'priority'
  WHERE status <> 'closed' AND owner <> '' AND owner <> 'nobody'
  ORDER BY owner, p.value, t.type, time

) AS tab