- ru
- Language: en
- Documentation version: 2.0
12. Find rows which have duplicate field values
Say you want all users whose first_name matches another user.
You can find duplicate records using the technique below.
>>> duplicates = User.objects.values(
'first_name'
).annotate(name_count=Count('first_name')).filter(name_count__gt=1)
>>> duplicates
<QuerySet [{'first_name': 'John', 'name_count': 3}]>
If you need to fill all the records, you can do
>>> records = User.objects.filter(first_name__in=[item['first_name'] for item in duplicates])
>>> print([item.id for item in records])
[2, 11, 13]