Question

我有很多关系，我试图查询返回一个或所有对象，但我能得到的最大值是该对象的id，它是我的Association Class Table的外键。

这是我的关联类表

class PolPropAssociation(db.Model):
    __tablename__ = 'polprop'
    politician =    db.Column(db.Integer, db.ForeignKey('politics.idPolitician'), primary_key=True)
    proposal =    db.Column(db.Integer, db.ForeignKey('proposals.idProposal'), primary_key=True)
    relation = db.Column(db.String(120))
    parent = db.relationship("Politic", back_populates="children")
    child = db.relationship("Proposal", back_populates="parents")
    draft = db.Column(db.Boolean, default=True)

    def __init__(self, relation):
        self.relation = relation.title()


class Politic(db.Model):
    __searchable__ = ['publicName', 'completeName']
    __tablename__ = 'politics'

    idPolitician = db.Column(db.Integer, primary_key=True)
    publicName = db.Column(db.String(150))
    completeName = db.Column(db.String(300))
    startDate = db.Column(db.Date, default=datetime.datetime.utcnow)
    endDate = db.Column(db.Date, default=datetime.datetime.utcnow)
    positions=db.relationship('Position',backref='pos_politic',lazy='select')
    draft = db.Column(db.Boolean, default = True)
    biolink = db.Column(db.String(200))
    flag = db.relationship('Flag', cascade="all, delete", backref='politics', lazy='dynamic')
    children = db.relationship("PolPropAssociation", back_populates="parent", lazy='dynamic')


class Proposal(db.Model):
    __tablename__ = 'proposals'

    idProposal = db.Column(db.Integer, primary_key=True)
    dateProposal = db.Column(db.Date, default=datetime.datetime.utcnow)
    description = db.Column(db.String(500))
    linkProposal = db.Column(db.String(200))
    idCategory = db.Column(db.Integer, db.ForeignKey('category.idcategory'))
    idProposalState = db.Column(db.Integer, db.ForeignKey('proposalstate.idproposalstate'))
    draft = db.Column(db.Boolean, default = True)
    flag = db.relationship('FlagProposal', backref='proposals', lazy='dynamic')
    parents = db.relationship("PolPropAssociation", back_populates="child", lazy='dynamic')

我想要回复一位政治家提出的所有建议，并提出idProposal：

proposal = Proposal.query.filter_by(idProposal=idProposal).first()
politicians = proposal.parents.all()

但它返回的是一个包含我的关联表的所有政治家列的数组。有什么方法可以用这些ID返回 Politic 对象吗？

祝你好运

Answer 1

我找到了解决方案：

如果有人询问如何使用对象关联表查询特定内容，请按照以下步骤进行：

pol = Politic.query.filter(Politic.children.any(proposal=idProposal)).all()

多对多查询对象

1 个答案: