python - sqlalchemy.exc.MultipleResultsFound : Multiple rows were found when exactly one was required

标签 python sql flask sqlalchemy flask-sqlalchemy

我在数据库中有这样的结构

tasks_exams = db.Table('tasks_exams',
    db.Column('task_id', db.Integer, db.ForeignKey('tasks.id')),
    db.Column('exam_id',  db.Integer, db.ForeignKey('exams.id'))
)

class Tasks(db.Model):
    __tablename__ = 'tasks'

    id        = db.Column(db.Integer, primary_key=True, autoincrement=True)
    task      = db.Column(db.Text)


class Exams(db.Model):
    __tablename__ = 'exams'

    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    name_of_Exam = db.Column(db.String(140))
    number_of_exam_task = db.Column(db.SmallInteger)
    name_of_exams_task = db.Column(db.String(140))

    tasks = db.relationship('Tasks',
                            secondary=tasks_exams,
                            back_populates="exams")

我想获取 exams_1 所在的所有任务:

tasku = Exams.query.filter(Exams.name_of_Exam == "exams_1").scalar()

我得到一个错误:

sqlalchemy.exc.MultipleResultsFound: Multiple rows were found when exactly one was required

我该如何解决我的问题?

最佳答案

tasku = Tasks.query.filter(Exams.name_of_Exam =="ЕГЭ").all()

关于python - sqlalchemy.exc.MultipleResultsFound : Multiple rows were found when exactly one was required,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/67382183/

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