尝试在 sqlalchemy => sqlalchemy.exc.OperationalError 中创建我的表时出错：(sqlite3.OperationalError) 没有这样的表：dht_new

Question

It cant find my db even tho i have created it wite create_table? I have tried to put the function create_Table" in diffrent places with no result? However i get the error,

sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) no such table: dht_new
[SQL: INSERT INTO dht_new (name) VALUES (?)]
[parameters: (None,)]

app.py

import os
from flask import Flask, request, jsonify
from flask_restful import Resource, Api
from flask_sqlalchemy import SQLAlchemy
from db import db


app = Flask(__name__)

app.config['SQLALCHEMY_DATABASE_URI'] = os.environ.get('SQLALCHEMY_DATABASE_URI', 'sqlite:///newdata.db')
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False

db = SQLAlchemy(app)

@app.before_first_request
def create_tables():
    db.create_all()


class fixdb(db.Model):
    __tablename__ = 'dht_new'

    id = db.Column(db.Integer, primary_key =True)
    name = db.Column(db.String(80))


    def __init__(self, temp):
        self.temp = temp

    def add_to_db(self):
        db.session.add(self)
        db.session.commit()


@app.route('/get', methods=['GET'])
def postrandom():
    temp = {'temperature': '23'}
    test_temp = fixdb(temp)

    test_temp.add_to_db()
    return jsonify(temp)



if __name__ == '__main__':
    from db import db
    db.init_app(app)
    app.run(port=5000, debug=True)

Answer 1

run.py

from app import app
from db import db

db.init_app(app)

@app.before_first_request
def create_tables():
    db.create_all()

Answer 2

You need to create table first in your SQLite database. You can use the SQLite Browser to do the same else use the python CLI to create the table. Since you didn't mention your .py file name so I can't exactly show you the code but it would be something like this
first type python in your terminal, then

from app import db
db.drop_all()
db.create_all()

and this should do it for you.