DatabaseError：字段“school_id”没有默认值

Question

I'm currently using mysqlalchemy, kivy, installer and main to take user input from a GUI and store it in an sql database. When trying to add data from my 'adding_data_for people'. This error occurs. I know the error is not in kivy but I bet it has something to do with the installer. Also I just want to store the data, nothing else. Sorry for the long and messy code pieces in advance.

    Traceback (most recent call last):
    File "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py", line 1246, in _execute_context
 cursor, statement, parameters, context
    File "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/default.py", line 588, in do_execute
 cursor.execute(statement, parameters)
    File "/usr/lib/python3.6/site-packages/mysql/connector/cursor.py", line 515, in execute
 self._handle_result(self._connection.cmd_query(stmt))
    File "/usr/lib/python3.6/site-packages/mysql/connector/connection.py", line 488, in cmd_query
 result = self._handle_result(self._send_cmd(ServerCmd.QUERY, query))
    File "/usr/lib/python3.6/site-packages/mysql/connector/connection.py", line 395, in _handle_result
 raise errors.get_exception(packet)
  mysql.connector.errors.DatabaseError: 1364 (HY000): Field 'school_id' doesn't have a default value

  The above exception was the direct cause of the following exception:

   Traceback (most recent call last):
   File "/home/cse/git/soft_161_homework/milestone_1/main.py", line 215, in <module>
 app.run()
   File "/usr/lib64/python3.6/site-packages/kivy/app.py", line 855, in run
 runTouchApp()
   File "/usr/lib64/python3.6/site-packages/kivy/base.py", line 504, in runTouchApp
 EventLoop.window.mainloop()
   File "/usr/lib64/python3.6/site-packages/kivy/core/window/window_sdl2.py", line 747, in mainloop
 self._mainloop()
   File "/usr/lib64/python3.6/site-packages/kivy/core/window/window_sdl2.py", line 479, in _mainloop
 EventLoop.idle()
   File "/usr/lib64/python3.6/site-packages/kivy/base.py", line 342, in idle
 self.dispatch_input()
   File "/usr/lib64/python3.6/site-packages/kivy/base.py", line 327, in dispatch_input
 post_dispatch_input(*pop(0))
   File "/usr/lib64/python3.6/site-packages/kivy/base.py", line 233, in post_dispatch_input
 listener.dispatch('on_motion', etype, me)
   File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
  File "/usr/lib64/python3.6/site-packages/kivy/core/window/__init__.py", line 1402, in on_motion
 self.dispatch('on_touch_down', me)
   File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
   File "/usr/lib64/python3.6/site-packages/kivy/core/window/__init__.py", line 1418, in on_touch_down
 if w.dispatch('on_touch_down', touch):
   File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
   File "/usr/lib64/python3.6/site-packages/kivy/uix/screenmanager.py", line 1191, in on_touch_down
 return super(ScreenManager, self).on_touch_down(touch)
   File "/usr/lib64/python3.6/site-packages/kivy/uix/widget.py", line 549, in on_touch_down
 if child.dispatch('on_touch_down', touch):
   File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
   File "/usr/lib64/python3.6/site-packages/kivy/uix/relativelayout.py", line 288, in on_touch_down
 ret = super(RelativeLayout, self).on_touch_down(touch)
   File "/usr/lib64/python3.6/site-packages/kivy/uix/widget.py", line 549, in on_touch_down
 if child.dispatch('on_touch_down', touch):
   File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
   File "/usr/lib64/python3.6/site-packages/kivy/uix/behaviors/button.py", line 151, in on_touch_down
 self.dispatch('on_press')
   File "kivy/_event.pyx", line 703, in kivy._event.EventDispatcher.dispatch
  File "kivy/_event.pyx", line 1214, in kivy._event.EventObservers.dispatch
  File "kivy/_event.pyx", line 1098, in kivy._event.EventObservers._dispatch
  File "/usr/lib64/python3.6/site-packages/kivy/lang/builder.py", line 64, in custom_callback
  exec(__kvlang__.co_value, idmap)
  File "/home/cse/git/soft_161_homework/milestone_1/schooltracking.kv", line 525, in <module>
 app.adding_data_for_people()
  File "/home/cse/git/soft_161_homework/milestone_1/main.py", line 184, in adding_data_for_people
 session.commit()
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/orm/session.py", line 1036, in commit
 self.transaction.commit()
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/orm/session.py", line 503, in commit
 self._prepare_impl()
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/orm/session.py", line 482, in _prepare_impl
 self.session.flush()
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/orm/session.py", line 2479, in flush
 self._flush(objects)
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/orm/session.py", line 2617, in _flush
 transaction.rollback(_capture_exception=True)
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/util/langhelpers.py", line 68, in __exit__
 compat.reraise(exc_type, exc_value, exc_tb)
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/util/compat.py", line 153, in reraise
 raise value
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/orm/session.py", line 2577, in _flush
 flush_context.execute()
   File "/usr/lib64/python3.6/site-packages/sqlalchemy/orm/unitofwork.py", line 422, in execute
 rec.execute(self)
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/orm/unitofwork.py", line 589, in execute
 uow,
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/orm/persistence.py", line 245, in save_obj
 insert,
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/orm/persistence.py", line 1137, in _emit_insert_statements
 statement, params
  File "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py", line 982, in execute
 return meth(self, multiparams, params)
 File "/usr/lib64/python3.6/site-packages/sqlalchemy/sql/elements.py", line 293, in _execute_on_connection
 return connection._execute_clauseelement(self, multiparams, params)
 File "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py", line 1101, in _execute_clauseelement
 distilled_params,
 File "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py", line 1250, in _execute_context
 e, statement, parameters, cursor, context
 File "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py", line 1476, in _handle_dbapi_exception
 util.raise_from_cause(sqlalchemy_exception, exc_info)
 File "/usr/lib64/python3.6/site-packages/sqlalchemy/util/compat.py", line 398, in raise_from_cause
 reraise(type(exception), exception, tb=exc_tb, cause=cause)
 File "/usr/lib64/python3.6/site-packages/sqlalchemy/util/compat.py", line 152, in reraise
 raise value.with_traceback(tb)
 File "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/base.py", line 1246, in _execute_context
 cursor, statement, parameters, context
 File "/usr/lib64/python3.6/site-packages/sqlalchemy/engine/default.py", line 588, in do_execute
 cursor.execute(statement, parameters)
 File "/usr/lib/python3.6/site-packages/mysql/connector/cursor.py", line 515, in execute
 self._handle_result(self._connection.cmd_query(stmt))
 File "/usr/lib/python3.6/site-packages/mysql/connector/connection.py", line 488, in cmd_query
 result = self._handle_result(self._send_cmd(ServerCmd.QUERY, query))
 File "/usr/lib/python3.6/site-packages/mysql/connector/connection.py", line 395, in _handle_result
 raise errors.get_exception(packet)
 sqlalchemy.exc.DatabaseError: (mysql.connector.errors.DatabaseError) 1364 (HY000): Field 'school_id' doesn't have a default value
[SQL: INSERT INTO person (home_id, name, grade_level) VALUES (%(home_id)s, %(name)s, %(grade_level)s)]
 [parameters: {'home_id': 1, 'name': 'qwd', 'grade_level': 8}]
 (Background on this error at: http://sqlalche.me/e/4xp6)

main.py

from kivy.app import App
from kivy.uix.label import Label
from kivy.modules import inspector  # For inspection
from kivy.core.window import Window  # For inspection
from kivy.uix.button import Button
from kivy.uix.screenmanager import ScreenManager, Screen
from sys import stderr
from sqlalchemy.exc import SQLAlchemyError
from sqlalchemy.exc import ProgrammingError
from schooltracking import SchoolTrackingDatabase, School, Home, Person
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.popup import Popup
from kivy.clock import Clock
from kivy.properties import ObjectProperty
from sqlalchemy.orm import sessionmaker
class SchoolTrackingApp(App):

def build(self):
    inspector.create_inspector(Window, self)


def __init__(self, **kwargs):
    super(SchoolTrackingApp, self).__init__(**kwargs)

    url = SchoolTrackingDatabase.construct_mysql_url('localhost', 3306, 'schooltracking', 'root', 'cse')
    self.schooltracking = SchoolTrackingDatabase(url)
    self.session = self.schooltracking.create_session()




def database_entries(self):


    query = self.session.query(School.names).all()
    query2 = self.session.query(School.district).all()

    text = self.root.ids.input_screen.text
    text2 = self.root.ids.input_screen2.text

    list_name = []
    for i in query:
        list_name.append(i[0])


    list_district = []
    for i in query2:
        list_district.append(i[0])

    for names in list_name:
        if text == names:
            for districts in list_district:
                if text2 == districts:
                    popup = Popup(title='School and District already in database',
                    content=Label(text=' Sorry, but it looks like that name and \ndistrict are already in our datbase. \nPlease create a new one.'),
                    size_hint=(None, None), size=(400, 400))
                    popup.open()

                    break


def blank_entries(self):
    text = self.root.ids.input_screen.text
    text2 = self.root.ids.input_screen2.text
    text3 = self.root.ids.input_screen3.text
    text4 = self.root.ids.input_screen4.text
    text5 = self.root.ids.input_screen5.text
    text6 = self.root.ids.input_screen6.text
    text7 = self.root.ids.input_screen7.text
    text8 = self.root.ids.input_screen8.text
    text9 = self.root.ids.input_screen9.text
    text10 = self.root.ids.input_screen10.text
    text11 = self.root.ids.input_screen.text
    text12 = self.root.ids.input_screen2.text
    text13 = self.root.ids.input_screen3.text
    text14 = self.root.ids.input_screen4.text
    text15 = self.root.ids.input_screen5.text
    text16 = self.root.ids.input_screen5.text
    text17 = self.root.ids.input_screen6.text
    text18 = self.root.ids.input_screen7.text
    text19 = self.root.ids.input_screen8.text
    text20 = self.root.ids.input_screen8.text
    text21 = self.root.ids.input_screen.text
    text22 = self.root.ids.input_screen2.text
    text23 = self.root.ids.input_screen3.text
    text24 = self.root.ids.input_screen4.text
    text25 = self.root.ids.input_screen4.text

    if text or text2 or text3 or text4 or text5 or text6 or text7 or text8 or text9 or text10 or text11 or text12 or text13 or text14 or text15 or text16 or text17 or text18 or text19 or text20 or text21 or text22 or text23 or text24 or text25== '':
        popup = Popup(title='No input given',
        content=Label(text=' The text boxes cannot be left blank!'),
        size_hint=(None, None), size=(400, 400))
        popup.open()


def NA_entry(self):
    text9 = self.root.ids.input_screen9.text
    if text9 != 'N/A':
        popup = Popup(title='Not N/A',
        content=Label(text=' The text box has to be N/A!'),
        size_hint=(None, None), size=(400, 400))
        popup.open()


def check_no_school_represents_child(self):

    query3 = self.session.query(Person.grade_level).all()
    query4 = self.session.query(Person.name).all()
    text10 = self.root.ids.input_screen10.text
    list_grade_levels = []
    for i in query3:
        list_grade_levels.append(i[0])

    list_names = []
    for i in query4:
        list_names.append(i[0])

    for names in list_names:
        for grade_level in list_grade_levels:
            if grade_level == None:
                popup = Popup(title='No school representing child',
                content=Label(text=' There is no school representing ' + names + ' in this home'),
                size_hint=(None, None), size=(400, 400))
                popup.open()
                break


def adding_data_for_school(self):
    url = SchoolTrackingDatabase.construct_mysql_url('localhost', 3306, 'schooltracking', 'root', 'cse')
    schooltracking = SchoolTrackingDatabase(url)
    schooltracking.ensure_tables_exist()

    session = schooltracking.create_session()
    add_data(session)
    session.commit()

    text = self.root.ids.input_screen.text
    text2 = self.root.ids.input_screen2.text
    text3 = self.root.ids.input_screen3.text



    schools = School(names=text, district=text2, education_level=text3)
    session.add(schools)
    session.commit()

def adding_data_for_home(self):
    url = SchoolTrackingDatabase.construct_mysql_url('localhost', 3306, 'schooltracking', 'root', 'cse')
    schooltracking = SchoolTrackingDatabase(url)
    schooltracking.ensure_tables_exist()

    session = schooltracking.create_session()
    add_data(session)
    session.commit()

    text4 = self.root.ids.input_screen4.text
    text20 = self.root.ids.input_screen20.text
    text21 = self.root.ids.input_screen21.text
    text22 = self.root.ids.input_screen22.text
    text23 = self.root.ids.input_screen23.text
    text24 = self.root.ids.input_screen24.text
    address = Home(school_id=1,first_address=text4, second_address=text20, city=text21, state_or_province=text22, postal_code=68118, country=text24)
    session.add(address)
    session.commit()

def adding_data_for_people(self):
    url = SchoolTrackingDatabase.construct_mysql_url('localhost', 3306, 'schooltracking', 'root', 'cse')
    schooltracking = SchoolTrackingDatabase(url)
    schooltracking.ensure_tables_exist()
    session = schooltracking.create_session()
    add_data(session)
    session.commit()
    text5 = self.root.ids.input_screen5.text
    text6 = self.root.ids.input_screen6.text
    text7 = self.root.ids.input_screen7.text
    text8 = self.root.ids.input_screen8.text
    text9 = self.root.ids.input_screen9.text

    person = Person(home_id=1, name=text5, grade_level=8)
    session.add(person)
    session.commit()


 def add_data(session):
     pass (This will add the data to the database do notneed to worry about this)


 def main():
    try:
    url = SchoolTrackingDatabase.construct_mysql_url('localhost', 3306, 'schooltracking', 'root', 'cse')
    schooltracking = SchoolTrackingDatabase(url)
    schooltracking.ensure_tables_exist()
    print('Tables created.')
    session = schooltracking.create_session()
    add_data(session)
    session.commit()
    print('Records created.')
    print('Your database has been successfully created!')
except (SQLAlchemyError) as exception:
    print('Database setup failed', file=stderr)
    print(f'Cause: {exception}', file=stderr)
    #if ProgrammingError:
        #print('Your credentials are incorrect with those matching to the database.' )

    exit(1)



if __name__ == '__main__':
   main()
   app = SchoolTrackingApp()
   app.run()

Installer

from sqlalchemy import create_engine, Column, Integer, String, DateTime, ForeignKfrom 
sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker, relationship

Persisted = declarative_base()


class School(Persisted):
    __tablename__ = 'schools'
    school_id = Column(Integer, primary_key=True)
    names = Column(String(256), nullable=False)
    district = Column(String(256), nullable=False)
    education_level = Column(String(256), nullable=False)
    homes = relationship('Home', uselist=True, back_populates='school')


class Home(Persisted):
    __tablename__ = 'homes'
    home_id = Column(Integer, primary_key=True)
    school_id = Column(Integer, ForeignKey('schools.school_id', ondelete='CASCADE'), nullable=False)
    first_address = Column(String(256), nullable=False)
    second_address = Column(String(256), nullable=True)
    city = Column(String(256), nullable=False)
    state_or_province = Column(String(256), nullable=False)
    postal_code = Column(String(256), nullable=False)
    country = Column(String(256), nullable=False)
    school = relationship('School', back_populates='homes')
    person = relationship('Person', back_populates='homes')


class Person(Persisted):
    __tablename__ = 'person'
    person_id = Column(Integer, primary_key=True)
    home_id = Column(Integer, ForeignKey('homes.home_id', ondelete='CASCADE'), nullable=False)
    name = Column(String(256), nullable=False)
    grade_level = Column(Integer, nullable=False)
    homes = relationship('Home', back_populates='person')


class SchoolTrackingDatabase(object):
    @staticmethod
    def construct_mysql_url(authority, port, database, username, password):
        return f'mysql+mysqlconnector://{username}:{password}@{authority}:{port}/{database}'

    @staticmethod
    def construct_in_memory_url():
        return 'sqlite:///'

    def __init__(self, url):
        self.engine = create_engine(url)  # an engine is like an endpoint, something to connect to
        self.Session = sessionmaker()  # create a class for connections to that endpoint / pylint: 
        disable=invalid-name
        self.Session.configure(bind=self.engine)  # associate the class with the endpoint

    def ensure_tables_exist(self):
        Persisted.metadata.create_all(self.engine)  # create tables for all subclasses of Persisted

    def create_session(self):
        return self.Session()  # create a new session, which is like a connection to the database

If the kivy file is needed please tell me:)

Answer 1

sqlalchemy.exc.DatabaseError: (mysql.connector.errors.DatabaseError) 1364 (HY000): Field 'school_id' doesn't have a default value
[SQL: INSERT INTO person (home_id, name, grade_level) VALUES (%(home_id)s, %(name)s, %(grade_level)s)]
 [parameters: {'home_id': 1, 'name': 'qwd', 'grade_level': 8}]

As the error says, you're trying to insert data in to a table without specifying school_id , which doesn't have a default value. You have two options:

1. When doing an insert, specify school_id .
2. Set a default value for school_id in the database.