Python 在SQLAchemy中创建表

以下代码用于创建名为users的新表：

engine = create_engine('mysql+pymysql://root:@localhost/sqlalchemy_tutorial', convert_unicode=True,echo=True)
db_session = scoped_session(sessionmaker(autocommit=False,
                                         autoflush=False,
                                         bind=engine))
Base = declarative_base()
Base.query = db_session.query_property()


Base = declarative_base()
from sqlalchemy import Column, Integer, String
class User(Base):
    __tablename__ = 'users'
    id = Column(Integer, primary_key=True)
    name = Column(String(50), unique=True)
    email = Column(String(120), unique=True)

    def __init__(self, name=None, email=None):
        self.name = name
        self.email = email

    def __repr__(self):
        return '<User %r>' % (self.name)


Base.metadata.create_all(bind=engine)

init.py

__author__ = 'Ricardo'
from models import User;

User.py

__author__ = 'Ricardo'
from sqlalchemy import Column, Integer, String
from application import Base
class User(Base):
    __tablename__ = 'users'
    id = Column(Integer, primary_key=True)
    name = Column(String(50), unique=True)
    email = Column(String(120), unique=True)

    def __init__(self, name=None, email=None):
        self.name = name
        self.email = email

    def __repr__(self):
        return '<User %r>' % (self.name)

---

您有一个循环导入：

\uuuu init\uuuu.py:2

→

User.py:3

（应该是

models.py

，不是吗？）→ <代码>应用程序.py:4→ <代码>模型.py。您应该导入模型类。尝试从模型中导入

。用户在
application.py中导入用户
，您有一个循环导入：
\uuuuuu init\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu→ 
User.py:3
（应该是
models.py
，不是吗？）→ <代码>应用程序.py:4
→ <代码>模型.py

。您应该导入模型类。从模型中尝试

。用户在
application.py中导入用户
__author__ = 'Ricardo'
from sqlalchemy import Column, Integer, String
from application import Base
class User(Base):
    __tablename__ = 'users'
    id = Column(Integer, primary_key=True)
    name = Column(String(50), unique=True)
    email = Column(String(120), unique=True)

    def __init__(self, name=None, email=None):
        self.name = name
        self.email = email

    def __repr__(self):
        return '<User %r>' % (self.name)

Base = declarative_base()
Base.query = db_session.query_property()
Base = declarative_base()
import models
#import models.User
#what else?
Base.metadata.create_all(bind=engine)