Last Record in Column, SQLALCHEMY

Question

I tried to get last record in my column using this

 ObjectRes.query.order_by('-id').first()

But the result is : None

I tried using all other queries, The only thing that works is

obj = ObjectRes.query.all()
return str(obj[-1].id)

The query is too heavy, Need lighter queries that work with this on Pythonanywhere. Thanks

Answer 1

Columns in SQLAlchemy models have methods attached to produce this behaviour. To order by ID descending, do this:

descending = Object.query.order_by(Object.id.desc())
last_item = descending.first()

Specifying Object.field is the clearest syntax for choosing a field to order by, and all columns / model attributes should support .desc() or .asc()

You can of course do this in a one liner as well:

last_item = Object.query.order_by(Object.id.desc()).first()