Python3-sqlalchemy-orm 创建多表关联表带外键

#-*-coding:utf-8-*-
#__author__ = "logan.xu"

import sqlalchemy
from sqlalchemy import create_engine,func
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Column,Integer,String,ForeignKey,DATE
from sqlalchemy.orm import sessionmaker,relationship

engine=create_engine("mysql+pymysql://root:12345678@localhost/news",encoding='utf-8',echo=True)
Base=declarative_base()

class Customer(Base):
    __tablename__ = 'customer'
    id = Column(Integer, primary_key=True)
    name = Column(String(64))

    # 以Address表id字段 设置两个外键
    billing_address_id = Column(Integer, ForeignKey("address.id"))
    shipping_address_id = Column(Integer, ForeignKey("address.id"))

    # relationship -允许你在Student表里通过backref字段反向查出所有它在表里的关联项-
    # foreign_keys=绑定外键 多次relationship 反差会识别不出指定数据所以添加foreign_keys参数。
    billing_address = relationship("Address",foreign_keys=[billing_address_id])
    shipping_address = relationship("Address",foreign_keys=[shipping_address_id])

class Address(Base):
    __tablename__ = 'address'
    id = Column(Integer, primary_key=True)
    street = Column(String(64))
    city = Column(String(64))
    state = Column(String(64))

    # 返回一个可以用来表示对象的可打印字符串
    def __repr__(self):
        return self.street

#---------------1.创建表-----------------#
# 创建表结构
Base.metadata.create_all(engine)
#---------------------------------------#

# bind=engine 绑定engine socket实例
#Session_class = sessionmaker(bind=engine)

# 生成session实例，如同pymysql内的cursor
#Session = Session_class()

#---------------2.写入数据-----------------#

# 写入数据
# addr1 = orm_fk.Address(street="Tiantongyuan",city="ChangPing",state="BJ")
# addr2 = orm_fk.Address(street="Wudaokou",city="Haidian",state="BJ")
# addr3 = orm_fk.Address(street="Yanjiao",city="Langfang",state="HB")

# 插入数据
# Session.add_all([addr1,addr2,addr3])

# 写入数据 并调用 Address字段插入数据 为 Customer数据
# c1 = orm_fk.Customer(name="kevin",billing_address=addr1,shipping_address=addr2)
# c2 = orm_fk.Customer(name="Jack",billing_address=addr3,shipping_address=addr3)

# 插入数据
# Session.add_all([c1,c2])
#---------------------------------------#

#---------------3.查询数据-----------------#

# 取出Customer内的 内存对象
#obj = Session.query(Customer).filter(Customer.name=="kevin").first()

# 通过内存 调用第一行name字段数据，
# 调用billing_address对应外键id的对应数据，
# 调用obj.shipping_address对应外键id的对应数据。
#print(obj.name,obj.billing_address,obj.shipping_address)
#---------------------------------------#

# 执行事务
#Session.commit()

/Users/drizzle/PycharmProjects/2018-12-03/venv/bin/python /Users/drizzle/PycharmProjects/2018-12-03/test_1/orm_api.py
2019-01-08 19:07:49,013 INFO sqlalchemy.engine.base.Engine SHOW VARIABLES LIKE 'sql_mode'
2019-01-08 19:07:49,013 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:07:49,015 INFO sqlalchemy.engine.base.Engine SHOW VARIABLES LIKE 'lower_case_table_names'
2019-01-08 19:07:49,015 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:07:49,017 INFO sqlalchemy.engine.base.Engine SELECT DATABASE()
2019-01-08 19:07:49,017 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:07:49,018 INFO sqlalchemy.engine.base.Engine show collation where `Charset` = 'utf8mb4' and `Collation` = 'utf8mb4_bin'
2019-01-08 19:07:49,018 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:07:49,020 INFO sqlalchemy.engine.base.Engine SELECT CAST('test plain returns' AS CHAR(60)) AS anon_1
2019-01-08 19:07:49,020 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:07:49,021 INFO sqlalchemy.engine.base.Engine SELECT CAST('test unicode returns' AS CHAR(60)) AS anon_1
2019-01-08 19:07:49,021 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:07:49,022 INFO sqlalchemy.engine.base.Engine SELECT CAST('test collated returns' AS CHAR CHARACTER SET utf8mb4) 
COLLATE utf8mb4_bin AS anon_1
2019-01-08 19:07:49,022 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:07:49,023 INFO sqlalchemy.engine.base.Engine DESCRIBE `customer`
2019-01-08 19:07:49,023 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:07:49,024 INFO sqlalchemy.engine.base.Engine DESCRIBE `address`
2019-01-08 19:07:49,024 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:07:49,030 INFO sqlalchemy.engine.base.Engine BEGIN (implicit)
2019-01-08 19:07:49,031 INFO sqlalchemy.engine.base.Engine INSERT INTO address (street, city, state) VALUES (%(street)s, %(city)s, %(state)s)
2019-01-08 19:07:49,031 INFO sqlalchemy.engine.base.Engine {'street': 'tiantongyuan', 'city': 'changping', 'state': 'BJ'}
2019-01-08 19:07:49,032 INFO sqlalchemy.engine.base.Engine INSERT INTO address (street, city, state) VALUES (%(street)s, %(city)s, %(state)s)
2019-01-08 19:07:49,032 INFO sqlalchemy.engine.base.Engine {'street': 'wudaokou', 'city': 'haidian', 'state': 'BJ'}
2019-01-08 19:07:49,033 INFO sqlalchemy.engine.base.Engine INSERT INTO address (street, city, state) VALUES (%(street)s, %(city)s, %(state)s)
2019-01-08 19:07:49,033 INFO sqlalchemy.engine.base.Engine {'street': 'yanjiao', 'city': 'langfang', 'state': 'BJ'}
2019-01-08 19:07:49,034 INFO sqlalchemy.engine.base.Engine INSERT INTO customer (name, billing_address_id, shipping_address_id) VALUES (%(name)s, 
%(billing_address_id)s, %(shipping_address_id)s)
2019-01-08 19:07:49,034 INFO sqlalchemy.engine.base.Engine {'name': 'Alex', 'billing_address_id': 1, 'shipping_address_id': 2}
2019-01-08 19:07:49,035 INFO sqlalchemy.engine.base.Engine INSERT INTO customer (name, billing_address_id, shipping_address_id) VALUES (%(name)s,
 %(billing_address_id)s, %(shipping_address_id)s)
2019-01-08 19:07:49,035 INFO sqlalchemy.engine.base.Engine {'name': 'Jack', 'billing_address_id': 3, 'shipping_address_id': 3}
2019-01-08 19:07:49,035 INFO sqlalchemy.engine.base.Engine COMMIT

Process finished with exit code 0

mysql> show tables;
+----------------+
| Tables_in_news |
+----------------+
| address        |
| customer       |
| student        |
| study_record   |
| user           |
+----------------+
5 rows in set (0.00 sec)

mysql> select * from customer;
+----+------+--------------------+---------------------+
| id | name | billing_address_id | shipping_address_id |
+----+------+--------------------+---------------------+
|  1 | Alex |                  1 |                   2 |
|  2 | Jack |                  3 |                   3 |
+----+------+--------------------+---------------------+
2 rows in set (0.00 sec)

mysql> select * from address;
+----+--------------+-----------+-------+
| id | street       | city      | state |
+----+--------------+-----------+-------+
|  1 | tiantongyuan | changping | BJ    |
|  2 | wudaokou     | haidian   | BJ    |
|  3 | yanjiao      | langfang  | BJ    |
+----+--------------+-----------+-------+
3 rows in set (0.00 sec)

#查询

#-*-coding:utf-8-*-
#__author__ = "logan.xu"

from test_1 import orm_many_fk
from sqlalchemy.orm import sessionmaker

Session_class=sessionmaker(bind=orm_many_fk.engine) #创建与数据库的链接
session= Session_class() #生成session实例 #cursor

#addr1=orm_many_fk.Address(street="tiantongyuan",city="changping",state="BJ")
#addr2=orm_many_fk.Address(street="wudaokou",city="haidian",state="BJ")
#add#r3=orm_many_fk.Address(street="yanjiao",city="langfang",state="BJ")
#
#session.add_all([addr1,addr2,addr3])
#c1= orm_many_fk.Customer(name="Alex",billing_address=addr1,shipping_address=addr2)
#c2= orm_many_fk.Customer(name="Jack",billing_address=addr3,shipping_address=addr3)

#session.add_all([c1,c2])

#查询
obj=session.query(orm_many_fk.Customer).filter(orm_many_fk.Customer.name=="alex").first()
print(obj.name,obj.billing_address,obj.shipping_address)

session.commit()

/Users/drizzle/PycharmProjects/2018-12-03/venv/bin/python /Users/drizzle/PycharmProjects/2018-12-03/test_1/orm_api.py
2019-01-08 19:15:17,840 INFO sqlalchemy.engine.base.Engine SHOW VARIABLES LIKE 'sql_mode'
2019-01-08 19:15:17,840 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:15:17,842 INFO sqlalchemy.engine.base.Engine SHOW VARIABLES LIKE 'lower_case_table_names'
2019-01-08 19:15:17,842 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:15:17,844 INFO sqlalchemy.engine.base.Engine SELECT DATABASE()
2019-01-08 19:15:17,844 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:15:17,844 INFO sqlalchemy.engine.base.Engine show collation where `Charset` = 'utf8mb4' and `Collation` = 'utf8mb4_bin'
2019-01-08 19:15:17,844 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:15:17,847 INFO sqlalchemy.engine.base.Engine SELECT CAST('test plain returns' AS CHAR(60)) AS anon_1
2019-01-08 19:15:17,847 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:15:17,848 INFO sqlalchemy.engine.base.Engine SELECT CAST('test unicode returns' AS CHAR(60)) AS anon_1
2019-01-08 19:15:17,848 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:15:17,849 INFO sqlalchemy.engine.base.Engine SELECT CAST('test collated returns' AS CHAR CHARACTER SET utf8mb4) 
COLLATE utf8mb4_bin AS anon_1
2019-01-08 19:15:17,849 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:15:17,850 INFO sqlalchemy.engine.base.Engine DESCRIBE `customer`
2019-01-08 19:15:17,850 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:15:17,851 INFO sqlalchemy.engine.base.Engine DESCRIBE `address`
2019-01-08 19:15:17,851 INFO sqlalchemy.engine.base.Engine {}
2019-01-08 19:15:17,857 INFO sqlalchemy.engine.base.Engine BEGIN (implicit)
2019-01-08 19:15:17,858 INFO sqlalchemy.engine.base.Engine SELECT customer.id AS customer_id, customer.name AS customer_name, 
customer.billing_address_id AS customer_billing_address_id, customer.shipping_address_id AS customer_shipping_address_id
FROM customer
WHERE customer.name = %(name_1)s
 LIMIT %(param_1)s
2019-01-08 19:15:17,858 INFO sqlalchemy.engine.base.Engine {'name_1': 'alex', 'param_1': 1}
2019-01-08 19:15:17,859 INFO sqlalchemy.engine.base.Engine SELECT address.id AS address_id, address.street AS address_street, 
address.city AS address_city, address.state AS address_state
FROM address
WHERE address.id = %(param_1)s
2019-01-08 19:15:17,860 INFO sqlalchemy.engine.base.Engine {'param_1': 1}
2019-01-08 19:15:17,861 INFO sqlalchemy.engine.base.Engine SELECT address.id AS address_id, address.street AS address_street, 
address.city AS address_city, address.state AS address_state
FROM address
WHERE address.id = %(param_1)s
2019-01-08 19:15:17,861 INFO sqlalchemy.engine.base.Engine {'param_1': 2}
Alex tiantongyuan wudaokou
2019-01-08 19:15:17,862 INFO sqlalchemy.engine.base.Engine COMMIT

Process finished with exit code 0