python - sqlalchemy.exc.ProgrammingError : (psycopg2. 编程错误)关系 "story"不存在

Question

这是我的代码如下。我正在尝试创建一个数据库，其中包含一个故事表。输入来自html输入部分

from flask import Flask, render_template
from flask_sqlalchemy import SQLAlchemy
from flask import request, redirect, url_for

app = Flask(__name__)
password = input("Your database password: ")
app.config['SQLALCHEMY_DATABASE_URI'] = 'postgresql://adambodnar:{}@localhost/user_stories'.format(password)
db = SQLAlchemy(app)

class Story(db.Model):
   id = db.Column(db.Integer, primary_key=True)
   story_title = db.Column(db.String(80), unique=True)
   user_story = db.Column(db.Text)
   acceptance_criteria = db.Column(db.Text)
   business_value = db.Column(db.Integer)
   estimation = db.Column(db.Integer)
   status = db.Column(db.String(30))

   def __init__(self, story_title, user_story, acceptance_criteria, business_value, estimation, status):
        self.story_title = story_title
        self.user_story = user_story
        self.acceptance_criteria = acceptance_criteria
        self.business_value = business_value
        self.estimation = estimation
        self.status = status


@app.route('/')
def index():
    return render_template('form.html')


@app.route('/story', methods=['POST'])
def story_post():
    new_story = Story(request.form['story_title'],request.form['user_story'], request.form['acceptance_criteria'], request.form['business_value'], request.form['estimation'], request.form['status'])


    db.session.add(new_story)
    db.session.commit()
    return redirect(url_for('index'))

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=8000)

当我尝试运行此程序时，出现以下错误:

sqlalchemy.exc.ProgrammingError: (psycopg2.ProgrammingError) relation "story" does not exist
LINE 1: INSERT INTO story (story_title, user_story, acceptance_crite...
                ^
 [SQL: 'INSERT INTO story (story_title, user_story, acceptance_criteria, business_value, estimation, status) VALUES (%(story_title)s, %(user_story)s, %(acceptance_criteria)s, %(business_value)s, %(estimation)s, %(status)s) RETURNING story.id'] [parameters: {'acceptance_criteria': 'asdasd', 'estimation': '1', 'user_story': 'asd', 'status': 'Planning', 'story_title': 'asd', 'business_value': '100'}]

故事表甚至没有创建，我通过pgAdmin检查了它。我尝试了很多方法，有些问题建议删除表，但它没有创建

Answer 1

您关注quickstart guide了吗？对于 Flask 和 sqlalchemy？不管怎样，在指南上你会注意到它说要这样做:

To create the initial database, just import the db object from an interactive Python shell and run the SQLAlchemy.create_all() method to create the tables and database:

>>> from yourapplication import db
>>> db.create_all()

在您的问题中包含的代码中，表创建代码似乎丢失了，这解释了未创建表的原因。

您可以考虑在您的应用程序中包含 db.create_all() (将其放在 db = SqlAlchemy(app) 之后) - 如果此包装器的功能类似于标准 sqlalchemy版本它应该只创建新表，如果表已经存在则不会炸毁。