SQLAlchemy - using hybrid properties in a query

Question

I am trying to use a SQLAlchemy hybrid property like this

class Metric(Base):
    __tablename__ = \'metric\'
    id = Column(Integer, primary_key=True)
    v         


        

Answer 1

You need to create expression

from sqlalchemy import func

class Metric(Base):
    __tablename__ = 'metric'
    id = Column(Integer, primary_key=True)
    value = Column(Float, nullable=False)

    @hybrid_property
    def dominance(self):
        return 1 - abs(0.5 - self.value)

    @dominance.expression
    def dominance(cls):
        return 1 - func.abs(0.5 - cls.value)