sqlalchemy写好数据库类，在mysql创建表问题，大佬们

2017-09-08 10:34:17 273 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

在Python3下怎样用Flask-SQLAlchemy对MySQL数据库操作现在让我们开始定义数据库模型。假设我们需要创建一个用户表来存储基本信息，可以在这里使用了SQLAlchemy提供的基本字段类型如StringInteger等来定义列属性，并通过建立与其他表之间的关系。通过本文，我们了解了如何在Python3环境下使用Flask-SQLAlchemy与MySQL数据库进行交互的基本流程，并探讨了一些优化性能的方法。希望这些知识能够帮助你在未来的项目中更加游刃有余地处理数据库操作。当然，实践出真知，只有不断尝试和总结经验，才能成为一名优秀的Web开发者。阅读详情

写了一个继承 declarative_base()的Base类，还有继承Base类的BaseModel类，同步数据库想让自动创建表，但是总是不能，问题出在哪里？



from sqlalchemy import create_engine, MetaData

from sqlalchemy.orm import sessionmaker

from sqlalchemy.ext.declarative import declarative_base



engine = create_engine('mysql+pymysql://root:123456@localhost:3306/Spider', echo=True)

Base = declarative_base()





class BaseModel(Base):

    __abstract__ = True

    __metadata__ = MetaData(bind=engine)

    __table_arhs__ = {

        'mysql_engine': 'InnoDb',

        'mysql_charset': 'utf8'

    }



if __name__ == '__main__':

    BaseModel.__metadata__.create_all()

其中一个表model类如下：



from sqlalchemy import Column

from sqlalchemy.dialects.mysql import INTEGER, VARCHAR



from common.db import BaseModel





class CityModel(BaseModel):

    __tablename__ = 'city'



    id = Column(INTEGER, primary_key=True)

    name = Column(VARCHAR(64))

打印出来的数据库命令信息如下



2017-09-08 22:24:15,737 INFO sqlalchemy.engine.base.Engine SHOW VARIABLES LIKE 'sql_mode'

2017-09-08 22:24:15,737 INFO sqlalchemy.engine.base.Engine {}

2017-09-08 22:24:15,750 INFO sqlalchemy.engine.base.Engine SELECT DATABASE()

2017-09-08 22:24:15,750 INFO sqlalchemy.engine.base.Engine {}

2017-09-08 22:24:15,751 INFO sqlalchemy.engine.base.Engine show collation where `Charset` = 'utf8' and `Collation` = 'utf8_bin'

2017-09-08 22:24:15,752 INFO sqlalchemy.engine.base.Engine {}

2017-09-08 22:24:15,753 INFO sqlalchemy.engine.base.Engine SELECT CAST('test plain returns' AS CHAR(60)) AS anon_1

2017-09-08 22:24:15,754 INFO sqlalchemy.engine.base.Engine {}

2017-09-08 22:24:15,754 INFO sqlalchemy.engine.base.Engine SELECT CAST('test unicode returns' AS CHAR(60)) AS anon_1

2017-09-08 22:24:15,754 INFO sqlalchemy.engine.base.Engine {}

2017-09-08 22:24:15,755 INFO sqlalchemy.engine.base.Engine SELECT CAST('test collated returns' AS CHAR CHARACTER SET utf8) COLLATE utf8_bin AS anon_1

2017-09-08 22:24:15,755 INFO sqlalchemy.engine.base.Engine {}

到底是那里的问题。。。

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