多用户加外键    

role_id=db.Column(db.Integer,db.ForeignKey('roles.id'))

一方角色加关系映射

users=db.relationship('Users',backref='roles')

from flaskimport Flask

from flask_scriptimport Manager

from flask_sqlalchemyimport SQLAlchemy

from flask_migrateimport Migrate,MigrateCommand

app=Flask(__name__)

manager=Manager(app)

db=SQLAlchemy(app)

migrate=Migrate(app,db)

manager.add_command('db',MigrateCommand)

class Config(object):

DEBUG=True

    SQLALCHEMY_DATABASE_URI='mysql://root:root@localhost:3306/flask01'

    SQLALCHEMY_TRACK_MODIFICATIONS=True

    SQLALCHEMY_COMMIT_ON_TEAR=True

    SQLALCHEMY_ECHO=True

app.config.from_object(Config)

class Roles(db.Model):

__tablename__='roles'

    id=db.Column(db.Integer,autoincrement=True,primary_key=True)

name=db.Column(db.String(20),nullable=False)

info=db.Column(db.String(50))

users=db.relationship('Users',backref='roles')

def __init__(self,name,info):

self.name=name

        self.info=info

    def __str__(self):

return "name *  %s  info * %s" %self.name,self.info

class Users(db.Model):

__tablename__='usrs'

    id=db.Column(db.Integer,autoincrement=True,primary_key=True)

name=db.Column(db.String(50),nullable=False)

pwd=db.Column(db.String(20),nullable=False)

role_id=db.Column(db.Integer,db.ForeignKey('roles.id'))

def __init__(self,name,pwd,role_id):

self.name=name

        self.pwd=pwd

        self.role_id=role_id

@app.route('/')

def  index():

return '

使用manager扩展命令来迁移数据库

'

if __name__ =='__main__':

manager.run()

控制台显示

(first_flask) D:\Flask项目设计\review_first>python apps.py db init

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:812: UserWarning: Neither SQ

LALCHEMY_DATABASE_URI nor SQLALCHEMY_BINDS is set. Defaulting SQLALCHEMY_DATABASE_URI to "sqlite:

///:memory:".

  warnings.warn(

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:833: FSADeprecationWarning:

SQLALCHEMY_TRACK_MODIFICATIONS adds significant overhead and will be disabled by default in the f

uture.  Set it to True or False to suppress this warning.

  warnings.warn(FSADeprecationWarning(

Creating directory D:\Flask项目设计\review_first\migrations ...  done

Creating directory D:\Flask项目设计\review_first\migrations\versions ...  done

Generating D:\Flask项目设计\review_first\migrations\alembic.ini ...  done

Generating D:\Flask项目设计\review_first\migrations\env.py ...  done

Generating D:\Flask项目设计\review_first\migrations\README ...  done

Generating D:\Flask项目设计\review_first\migrations\script.py.mako ...  done

Please edit configuration/connection/logging settings in 'D:\\Flask项目设计\\review_first\\migrat

ions\\alembic.ini' before proceeding.

(first_flask) D:\Flask项目设计\review_first>python apps.py db migrate

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:812: UserWarning: Neither SQ

LALCHEMY_DATABASE_URI nor SQLALCHEMY_BINDS is set. Defaulting SQLALCHEMY_DATABASE_URI to "sqlite:

///:memory:".

  warnings.warn(

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:833: FSADeprecationWarning:

SQLALCHEMY_TRACK_MODIFICATIONS adds significant overhead and will be disabled by default in the f

uture.  Set it to True or False to suppress this warning.

  warnings.warn(FSADeprecationWarning(

INFO  [alembic.runtime.migration] Context impl MySQLImpl.

INFO  [alembic.runtime.migration] Will assume non-transactional DDL.

INFO  [alembic.autogenerate.compare] Detected added table 'roles'

Generating D:\Flask项目设计\review_first\migrations\versions\2ce58beca98f_.py ...  done

(first_flask) D:\Flask项目设计\review_first>python apps.py db upgrade

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:812: UserWarning: Neither SQ

LALCHEMY_DATABASE_URI nor SQLALCHEMY_BINDS is set. Defaulting SQLALCHEMY_DATABASE_URI to "sqlite:

///:memory:".

(first_flask) D:\Flask项目设计\review_first>python apps.py db migrate

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:812: UserWarning: Neither SQ

LALCHEMY_DATABASE_URI nor SQLALCHEMY_BINDS is set. Defaulting SQLALCHEMY_DATABASE_URI to "sqlite:

///:memory:".

  warnings.warn(

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:833: FSADeprecationWarning:

SQLALCHEMY_TRACK_MODIFICATIONS adds significant overhead and will be disabled by default in the f

uture.  Set it to True or False to suppress this warning.

  warnings.warn(FSADeprecationWarning(

INFO  [alembic.runtime.migration] Context impl MySQLImpl.

INFO  [alembic.runtime.migration] Will assume non-transactional DDL.

INFO  [alembic.autogenerate.compare] Detected added column 'roles.info'

Generating D:\Flask项目设计\review_first\migrations\versions\51108d4647a0_.py ...  done

(first_flask) D:\Flask项目设计\review_first>python apps.py db upgrade

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:812: UserWarning: Neither SQ

LALCHEMY_DATABASE_URI nor SQLALCHEMY_BINDS is set. Defaulting SQLALCHEMY_DATABASE_URI to "sqlite:

///:memory:".

  warnings.warn(

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:833: FSADeprecationWarning:

SQLALCHEMY_TRACK_MODIFICATIONS adds significant overhead and will be disabled by default in the f

uture.  Set it to True or False to suppress this warning.

  warnings.warn(FSADeprecationWarning(

INFO  [alembic.runtime.migration] Context impl MySQLImpl.

(first_flask) D:\Flask项目设计\review_first>python apps.py db migrate

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:812: UserWarning: Neither SQ

LALCHEMY_DATABASE_URI nor SQLALCHEMY_BINDS is set. Defaulting SQLALCHEMY_DATABASE_URI to "sqlite:

///:memory:".

  warnings.warn(

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:833: FSADeprecationWarning:

SQLALCHEMY_TRACK_MODIFICATIONS adds significant overhead and will be disabled by default in the f

uture.  Set it to True or False to suppress this warning.

  warnings.warn(FSADeprecationWarning(

INFO  [alembic.runtime.migration] Context impl MySQLImpl.

INFO  [alembic.runtime.migration] Will assume non-transactional DDL.

INFO  [alembic.autogenerate.compare] Detected added table 'usrs'

Generating D:\Flask项目设计\review_first\migrations\versions\f042b5b9b41c_.py ...  done

(first_flask) D:\Flask项目设计\review_first>python apps.py db upgrade

D:\python\first_flask\lib\site-packages\flask_sqlalchemy\__init__.py:812: UserWarning: Neither SQL

SQLALCHEMY_TRACK_MODIFICATIONS adds significant overhead and will be disabled by default in the f

uture.  Set it to True or False to suppress this warning.

  warnings.warn(FSADeprecationWarning(

INFO  [alembic.runtime.migration] Context impl MySQLImpl.

INFO  [alembic.runtime.migration] Will assume non-transactional DDL.

INFO  [alembic.runtime.migration] Running upgrade 51108d4647a0 -> f042b5b9b41c, empty message