hybrid_expressions 在带参数的 SQLAlchemy 中

Question

我目前在我概述的模型上有以下 hybrid_property 和 hybrid_property.expression()：

class Body():

    @hybrid_property
    def altitude(self, LST: float, latitude: float) -> float:
        return self.get_altitude(LST, latitude)

    @altitude.expression
    def altitude(cls, LST: float, latitude: float) -> float:
        """
        Get the altitude of the star as a raw SQL expressions
        """
        ha = (LST - cls.ra) % 360

        ra = func.radians(ha)

        dec = func.radians(cls.dec)

        lat = func.radians(latitude)

        alt = func.asin(
            func.sin(dec) * func.sin(lat) + func.cos(dec) * func.cos(lat) * func.cos(ra)
        )

        return func.degrees(alt)

但是，当我尝试在 SQLAlchemy 过滤器中使用它时：

query = query.filter(self.model.altitude(LST, latitude) > 0)

我收到以下错误：

TypeError: altitude() missing 2 required positional arguments: 'LST' and 'latitude'

即使它们都已定义。

Answer 1

您正在查找 hybrid_method，hybrid_property 不支持参数。

class Body():

    @hybrid_method
    def altitude(self, LST: float, latitude: float) -> float:
        return self.get_altitude(LST, latitude)

    @altitude.expression
    def altitude(self, LST: float, latitude: float) -> float:
        """
        Get the altitude of the star as a raw SQL expressions
        """
        ha = (LST - cls.ra) % 360

        ra = func.radians(ha)

        dec = func.radians(cls.dec)

        lat = func.radians(latitude)

        alt = func.asin(
            func.sin(dec) * func.sin(lat) + func.cos(dec) * func.cos(lat) * func.cos(ra)
        )

        return func.degrees(alt)

hybrid_expressions 在带参数的 SQLAlchemy 中

hybrid_expressions in SQLAlchemy with arguments

python

sqlalchemy