Django models : Inverted index on timestamp with query for 'n' latest rows

Question

I have the datetime filled with auto_now=True
Database is mysql.
Range queries won't work for me directly.
Is there any one liner for this?

For simplicity, how can I get 10 rows with highest values for a field(let it be Integerfield) ?

Answer 1

order by the field in descending order and limit to 10?

ORDER BY fieldname DESC LIMIT 10

Answer 2

For model Model with integer field field, this should work:

top10 = Model.objects.order_by('-field')[:10]

If you want django to have an index on the field, you need to define it in the model with db_index option:

class Model(models.Model):
    field = IntegerField(db_index=True)

Regular database index should work even if your asking for the highest values.