我有个问题。我必须做这个查询:
@app.route('/api/subscriptions/<string:id>', methods=('DELETE',))
@decorators.login_required
def delete_subscription(id):
dbsession = DBSession()
session = Session()
favorit = (dbsession.query(StudentsFavorites)
.filter(Exams.number == str(id))
.filter(StudentsFavorites.exam_id)
.filter(Students.id == StudentsFavorites.student_id)
.filter(Students.id == str(session.get_user_id()))
.delete() )
dbsession.flush()
return jsonify(error=False)
但是当我做这个查询时,我得到了这个异常:
OperationalError: (OperationalError) no such column: exams.number u'DELETE FROM students_favorites WHERE exams.number = ? AND students_favorites.exam_id AND students.id = students_favorites.student_id AND students.id = ?' ('123123123', 'a24213')
桌子很大,有很多信息,所以我不能全部发布。但是这个查询有效:
@app.route('/api/subscriptions/<string:id>', methods=('PUT',))
@decorators.login_required
def add_subscription(id):
dbsession = DBSession()
session = Session()
examID = (dbsession.query(Exams.id)
.filter(Exams.number == id).first()
)
favorit=StudentsFavorites(student_id=session.get_user_id(), exam_id=examID.id)
dbsession.add(favorit)
dbsession.flush()
return jsonify(error=False)
表格的简短视图:
table: Exams
rows: id, number (number is the id i put into the function)
table: StudentsFavorites
rows: student_id, exams_id
table: Students
rows: id
我真的不明白,为什么他没有找到异常中的数字行。
编辑:
数据库学生最爱:
class StudentsFavorites(Base):
"""N:M resolve model for the exams to the semester.
"""
__tablename__ = "students_favorites"
student_id = Column(Unicode(255), ForeignKey("students.id"), primary_key=True, autoincrement=False)
exam_id = Column(Integer, ForeignKey("exams.id"), primary_key=True, autoincrement=False)
created_at = Column(DateTime, nullable = False, default = datetime.now)
student = relationship("Students", uselist = False, lazy="joined")
exam = relationship("Exams", uselist=False, lazy="joined")
像这样的东西?我试过这个:
(dbsession.query(StudentsFavorites)
.filter(StudentsFavorites.exam.id == str(id))
.filter(StudentsFavorites.student.id == str(session.get_user_id()))
.delete()
)
但是得到了错误,那个 id 在考试/学生中不存在