m2m

flask sqlalchemy many to many relationship with extra field

由 流过昼夜 提交于 2020-12-29 09:11:57
问题 I have 2 tables: restaurants and foods, and a 3rd table restaurants_foods which stores the many to many relationship between the 2 tables restaurants_foods = db.Table('restaurants_foods', db.Column('restaurant_id', db.Integer, db.ForeignKey('restaurants.id'), primary_key=True), db.Column('food_id', db.Integer, db.ForeignKey('foods.id'), primary_key=True), db.Column('food_price', db.Float) ) class Food(Model): __tablename__ = "foods" id = db.Column(db.Integer, primary_key=True, autoincrement

flask sqlalchemy many to many relationship with extra field

由 微笑、不失礼 提交于 2020-12-29 09:11:57
问题 I have 2 tables: restaurants and foods, and a 3rd table restaurants_foods which stores the many to many relationship between the 2 tables restaurants_foods = db.Table('restaurants_foods', db.Column('restaurant_id', db.Integer, db.ForeignKey('restaurants.id'), primary_key=True), db.Column('food_id', db.Integer, db.ForeignKey('foods.id'), primary_key=True), db.Column('food_price', db.Float) ) class Food(Model): __tablename__ = "foods" id = db.Column(db.Integer, primary_key=True, autoincrement

flask sqlalchemy many to many relationship with extra field

由 谁说胖子不能爱 提交于 2020-12-29 09:06:31
问题 I have 2 tables: restaurants and foods, and a 3rd table restaurants_foods which stores the many to many relationship between the 2 tables restaurants_foods = db.Table('restaurants_foods', db.Column('restaurant_id', db.Integer, db.ForeignKey('restaurants.id'), primary_key=True), db.Column('food_id', db.Integer, db.ForeignKey('foods.id'), primary_key=True), db.Column('food_price', db.Float) ) class Food(Model): __tablename__ = "foods" id = db.Column(db.Integer, primary_key=True, autoincrement

flask sqlalchemy many to many relationship with extra field

由 天大地大妈咪最大 提交于 2020-12-29 09:06:20
问题 I have 2 tables: restaurants and foods, and a 3rd table restaurants_foods which stores the many to many relationship between the 2 tables restaurants_foods = db.Table('restaurants_foods', db.Column('restaurant_id', db.Integer, db.ForeignKey('restaurants.id'), primary_key=True), db.Column('food_id', db.Integer, db.ForeignKey('foods.id'), primary_key=True), db.Column('food_price', db.Float) ) class Food(Model): __tablename__ = "foods" id = db.Column(db.Integer, primary_key=True, autoincrement

Mqtt client disconnects when another client connects to the server

由 不打扰是莪最后的温柔 提交于 2020-11-28 03:43:07
问题 I am new to MQTT messaging system, but yet i managed to implement the paho Android service in snapdragon board running AOSP kk-4.4.2 . My service will start at the boot up and it will connect to the public broker of HiveMQ with port 1883 . The problem is after connecting my Android device running my custom AOSP to the server and if i try to connect another client from the android application which is running on a phone. The client in the snapdragon board automatically disconnects from the

Mqtt client disconnects when another client connects to the server

由 断了今生、忘了曾经 提交于 2020-11-28 03:38:44
问题 I am new to MQTT messaging system, but yet i managed to implement the paho Android service in snapdragon board running AOSP kk-4.4.2 . My service will start at the boot up and it will connect to the public broker of HiveMQ with port 1883 . The problem is after connecting my Android device running my custom AOSP to the server and if i try to connect another client from the android application which is running on a phone. The client in the snapdragon board automatically disconnects from the

Mqtt client disconnects when another client connects to the server

由 谁说胖子不能爱 提交于 2020-11-28 03:38:29
问题 I am new to MQTT messaging system, but yet i managed to implement the paho Android service in snapdragon board running AOSP kk-4.4.2 . My service will start at the boot up and it will connect to the public broker of HiveMQ with port 1883 . The problem is after connecting my Android device running my custom AOSP to the server and if i try to connect another client from the android application which is running on a phone. The client in the snapdragon board automatically disconnects from the

Mqtt client disconnects when another client connects to the server

由 喜夏-厌秋 提交于 2020-06-17 09:51:27
问题 I am new to MQTT messaging system, but yet i managed to implement the paho Android service in snapdragon board running AOSP kk-4.4.2 . My service will start at the boot up and it will connect to the public broker of HiveMQ with port 1883 . The problem is after connecting my Android device running my custom AOSP to the server and if i try to connect another client from the android application which is running on a phone. The client in the snapdragon board automatically disconnects from the

Mqtt client disconnects when another client connects to the server

由 我的未来我决定 提交于 2020-06-17 09:51:12
问题 I am new to MQTT messaging system, but yet i managed to implement the paho Android service in snapdragon board running AOSP kk-4.4.2 . My service will start at the boot up and it will connect to the public broker of HiveMQ with port 1883 . The problem is after connecting my Android device running my custom AOSP to the server and if i try to connect another client from the android application which is running on a phone. The client in the snapdragon board automatically disconnects from the

sqlalchemy 多对多关系

由 本小妞迷上赌 提交于 2020-03-17 04:45:27
一、前言 　　多对多的关系是一张表可以关联多张表。　 　　现在来设计一个能描述“图书”与“作者”的关系的表结构，需求是 一本书可以有好几个作者一起出版 一个作者可以写好几本书 二、表结构和数据 　　 book_m2m_author表由author表和book表生成 三、事例 from sqlalchemy import Table, Column, Integer, String, DATE, ForeignKey from sqlalchemy.orm import relationship from sqlalchemy.ext.declarative import declarative_base from sqlalchemy import create_engine # 如果插入数据有中文，需要指定 charset=utf8 engine = create_engine("mysql+pymysql://bigberg:111111@172.16.200.49:3306/study?charset=utf8", encoding='utf-8') Base = declarative_base() # 创建orm基类 Base.metadata.create_all(engine) # 这个表的创建后，不需要维护 book_m2m_author = Table("book
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