q_left = (Q(**{'%s__isnull' % prefix_debut : True}) | Q(**{'%s__lte' % prefix_debut : date_debut})) & (Q(**{'%s__gte' % prefix_fin : date_debut}) & Q(**{'%s__lte' % prefix_fin : date_fin}))
q_right = (Q(**{'%s__isnull' % prefix_fin : True}) | Q(**{'%s__gte' % prefix_fin : date_fin})) & (Q(**{'%s__gte' % prefix_debut : date_debut}) & Q(**{'%s__lte' % prefix_debut : date_fin}))
q_both = Q(**{'%s__isnull' % prefix_fin : True}) | Q(**{'%s__lte' % prefix_fin : date_fin}) & (Q(**{'%s__isnull' % prefix_debut : True}) | Q(**{'%s__gte' % prefix_debut : date_debut}))
- qs = qs.filter(q_left | q_right | q_both)
+ qs = qs.filter(q_left | q_right | q_both).distinct()
self.params = old
return qs