Query a specific JSON column (postgres) with sqlalchemy

Question

I have a model with a JSON field:

class Item(db.Model)
   ...
   data = db.Column(JSON, nullable=False)
   ...

The data contains some JSON

Answer 1

You need to use Float instead of Integer as argument of cast

db.session.query(func.count(Item)).filter(
          Item.data['surcharge'].cast(Float) > 1
      ).all()