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フォーム データ フォームを mysql データベースに送信するときに、次のエラーに完全に行き詰まりました。手がかりに非常に感謝しています。

次のエラーが表示されます。

"sqlalchemy.orm.exc.FlushError FlushError: インスタンスに NULL ID キーがあります。これが自動生成された値である場合は、データベース テーブルで新しい主キー値の生成が許可されていること、およびマップされた列オブジェクトがこれらを期待するように構成されていることを確認してください。また、load() イベント内など、不適切な時間にこの flush() が発生していないことも確認してください。」

コードは次のとおりです。

from flask import Flask, request,redirect,render_template,flash
from wtforms import Form, TextField, BooleanField
from wtforms.validators import Required
from flask.ext.sqlalchemy import SQLAlchemy

app = Flask(__name__)
db = SQLAlchemy(app)

app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://root:@127.0.0.1/Jungle'

class Sighting(db.Model):
    __tablename__ = 'Animals'
    animal_name = db.Column(db.String, primary_key = True)
    animal_type = db.Column(db.String)
    scary = db.Column(db.String)

class LoginForm(Form):
    animal_name = TextField('Animal')
    animal_type = TextField('Type')
    scary = BooleanField('Scary')

@app.route('/login',methods = ['GET','POST'])
def login():
    form = LoginForm()    
    if request.method == 'POST':
        newanimal = Sighting(animal_name=form.animal_name.data,animal_type=form.animal_type.data,scary=form.scary.data)
        db.session.add(newanimal)
        db.session.commit()
        return redirect('/thanks')
    elif request.method == 'GET':
        return render_template('login.html', form = form)

@app.route('/thanks',methods= ['GET'])
def thanks():
    return render_template('thanks.html')

if __name__ == '__main__':
  app.run(debug=True)

上記のコードで次のようなものを実行すると、機能し、データベースに正常にコミットされます。

@app.route('/submit',methods =['GET'])
def submit():
    newanimal = Sighting(animal_name='frog',animal_type='amphibian', scary='No')
    db.session.add(newanimal)
    db.session.commit()
    return render_template('thanks.html')

ということで、フォームデータと関係があるようです。MySQL テーブルは次のとおりです。

CREATE TABLE `Animals` (
  `animal_name` varchar(100) DEFAULT NULL,
  `animal_type` varchar(100) DEFAULT NULL,
  `scary` varchar(100) DEFAULT NULL,
  `id` int(11) NOT NULL AUTO_INCREMENT,
  PRIMARY KEY (`id`),
  UNIQUE KEY `id` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=21 DEFAULT CHARSET=utf8

失敗した送信のいずれかが発生した場合でも、データベース テーブルは自動インクリメントするようです。手動で行を挿入すると、その ID は前のものよりも少し高くなります。テーブルには、すべてのフィールドが null の行が 1 つあります。

よろしくお願いします！

(奇妙な命名スキーマを許してください - チュートリアルから適応されています)

sqlalchemy.orm.exc.FlushError
FlushError: Instance <Sighting at 0x10c6552d0> has a NULL identity key.  If this is an auto-generated value, check that the database table allows generation of new primary key values, and that the mapped Column object is configured to expect these generated values.  Ensure also that this flush() is not occurring at an inappropriate time, such aswithin a load() event.

Traceback (most recent call last)
File "/Library/Python/2.7/site-packages/flask/app.py", line 1836, in __call__
return self.wsgi_app(environ, start_response)
File "/Library/Python/2.7/site-packages/flask/app.py", line 1820, in wsgi_app
response = self.make_response(self.handle_exception(e))
File "/Library/Python/2.7/site-packages/flask/app.py", line 1403, in handle_exception
reraise(exc_type, exc_value, tb)
File "/Library/Python/2.7/site-packages/flask/app.py", line 1817, in wsgi_app
response = self.full_dispatch_request()
File "/Library/Python/2.7/site-packages/flask/app.py", line 1477, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/Library/Python/2.7/site-packages/flask/app.py", line 1381, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/Library/Python/2.7/site-packages/flask/app.py", line 1475, in full_dispatch_request
rv = self.dispatch_request()
File "/Library/Python/2.7/site-packages/flask/app.py", line 1461, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "/Users/tomhalloran/TomDev/FlaskSkint/learnv3.py", line 29, in login
db.session.commit()
File "/Library/Python/2.7/site-packages/sqlalchemy/orm/scoping.py", line 149, in do
return getattr(self.registry(), name)(*args, **kwargs)
File "/Library/Python/2.7/site-packages/sqlalchemy/orm/session.py", line 765, in commit
self.transaction.commit()
File "/Library/Python/2.7/site-packages/sqlalchemy/orm/session.py", line 370, in commit
self._prepare_impl()
File "/Library/Python/2.7/site-packages/sqlalchemy/orm/session.py", line 350, in _prepare_impl
self.session.flush()
File "/Library/Python/2.7/site-packages/sqlalchemy/orm/session.py", line 1879, in flush
self._flush(objects)
File "/Library/Python/2.7/site-packages/sqlalchemy/orm/session.py", line 1997, in _flush
transaction.rollback(_capture_exception=True)
File "/Library/Python/2.7/site-packages/sqlalchemy/util/langhelpers.py", line 57, in __exit__
compat.reraise(exc_type, exc_value, exc_tb)
File "/Library/Python/2.7/site-packages/sqlalchemy/orm/session.py", line 1967, in _flush
flush_context.finalize_flush_changes()
File "/Library/Python/2.7/site-packages/sqlalchemy/orm/unitofwork.py", line 387, in finalize_flush_changes
self.session._register_newly_persistent(other)
File "/Library/Python/2.7/site-packages/sqlalchemy/orm/session.py", line 1389, in _register_newly_persistent
% state_str(state)
FlushError: Instance <Sighting at 0x10c6552d0> has a NULL identity key. If this is an auto-generated value, check that the database table allows generation of new primary key values, and that the mapped Column object is configured to expect these generated values. Ensure also that this flush() is not occurring at an inappropriate time, such aswithin a load() event.
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