quick_orm 0.2.3

A python orm which enables you to get started in less than a minute! Super easy to setup and super easy to use, yet super powerful! You would regret that you didn't discorver it earlier!

Introduction
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A python ORM which enables you to get started in less than a minute!
Super easy to setup and super easy to use, yet super powerful!
You would regret that you didn't discorver it earlier!



Features
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- quick: you could get and play with it in less than a minute. It couldn't be more straightforward.
- easy: you don't have to write any SQL statements, including those "create table xxx ..." ones.
- simple: the core code counts only 230 lines including comments and pydocs, bugs have nowhere to hide.
- free: released under BSD license, you are free to use it and distribute it.
- powerful: built upon SQLAlchemy and doesn't compromise its power.
- support relationships by means of python decorators.
- support table inheritance in a most natural way.
- support multiple databases: you can map your models to many databases without difficulty.
- write less, do more: taking advantage of python metaclass reduces data modeling code dramatically.
- long-term maintained: Continous efforts are taking to improve and maintain it.



Prerequisites
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You need Python 2.6 or above. I haven't test it against Python 3+. I will do it soon.
Quick ORM depends on SQLAlchemy 0.7+. I haven't tested it against older versions of SQLAlchemy.
Quick ORM also depends on toolkit_library 0.3.1+
If you are using pip to manage python packages, you don't have to install SQLAlchemy or toolkit_library separately.
The prerequisites will be installed automatically by pip.



How to install or upgrade ?
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Just one command:
pip install --upgrade quick_orm
Alternatively you could download the source code and issue command: python setup.py install
If you choose to install from source code, you have to install the prerequisites manually.



Hello World example
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from quick_orm.core import Database
from sqlalchemy import Column, String

class User(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(30))

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()

user = User(name = 'Hello World')
db.session.add_then_commit(user)

user = db.session.query(User).get(1)
print 'My name is', user.name



Foreign key example
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from quick_orm.core import Database
from sqlalchemy import Column, String, Text

class Question(object):
__metaclass__ = Database.DefaultMeta
title = Column(String(70))
content = Column(Text)

@Database.foreign_key(Question)
class Answer(object):
__metaclass__ = Database.DefaultMeta
content = Column(Text)

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()

question = Question(title = 'What is Quick ORM ?', content = 'What is Quick ORM ?')
answer = Answer(question = question, content = 'Quick ORM is a python ORM which enables you to get started in less than a minute!')
db.session.add_then_commit(answer)

question = db.session.query(Question).get(1)
print 'The question is:', question.title
print 'The answer is:', question.answers.first().content



Foreign key options example
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from quick_orm.core import Database
from sqlalchemy import Column, String, Text

class Question(object):
__metaclass__ = Database.DefaultMeta
title = Column(String(70))
content = Column(Text)

@Database.foreign_key(Question, ref_name = 'question', backref_name = 'answers')
class Answer(object):
__metaclass__ = Database.DefaultMeta
content = Column(Text)

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()

question = Question(title = 'What is Quick ORM ?', content = 'What is Quick ORM ?')
answer = Answer(question = question, content = 'Quick ORM is a python ORM which enables you to get started in less than a minute!')
db.session.add_then_commit(answer)

question = db.session.query(Question).get(1)
print 'The question is:', question.title
print 'The answer is:', question.answers.first().content



Foreign key to oneself example
******************************
from quick_orm.core import Database
from sqlalchemy import Column, String

@Database.foreign_key('Node', ref_name = 'parent_node', backref_name = 'children_nodes')
class Node(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(70))

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()

root_node = Node(name = 'root')
node1 = Node(name = 'node1', parent_node = root_node)
node2 = Node(name = 'node2', parent_node = root_node)
db.session.add_then_commit(root_node)

root_node = db.session.query(Node).filter_by(name = 'root').one()
print 'Root node have {0} children nodes, they are {1}'\
.format(root_node.children_nodes.count(), ', '.join(node.name for node in root_node.children_nodes))



Many-to-many relationship example
*********************************
from quick_orm.core import Database
from sqlalchemy import Column, String

class User(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(30))

@Database.many_to_many(User)
class Role(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(30))

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()

user1 = User(name = 'Tyler Long')
user2 = User(name = 'Peter Lau')
role = Role(name = 'Administrator', users = [user1, user2])
db.session.add_then_commit(role)

admin_role = db.session.query(Role).filter_by(name = 'Administrator').one()
print ', '.join([user.name for user in admin_role.users]), 'are admintrators'



Many-to-many relationship options example
*****************************************
from quick_orm.core import Database
from sqlalchemy import Column, String

class User(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(30))

@Database.many_to_many(User, ref_name = 'users', backref_name = 'roles', middle_table_name = 'user_role')
class Role(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(30))

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()

user1 = User(name = 'Tyler Long')
user2 = User(name = 'Peter Lau')
role = Role(name = 'Administrator', users = [user1, user2])
db.session.add_then_commit(role)

admin_role = db.session.query(Role).filter_by(name = 'Administrator').one()
print ', '.join([user.name for user in admin_role.users]), 'are admintrators'



Many-to-many relationship with oneself example
**********************************************
from quick_orm.core import Database
from sqlalchemy import Column, String

@Database.many_to_many('User', ref_name = 'users_i_follow', backref_name = 'users_follow_me')
class User(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(30))

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()

peter = User(name = 'Peter Lau')
mark = User(name = 'Mark Wong', users_i_follow = [peter, ])
tyler = User(name = 'Tyler Long', users_i_follow = [peter, ], users_follow_me = [mark, ])
db.session.add_then_commit(tyler)

tyler = db.session.query(User).filter_by(name = 'Tyler Long').one()
print 'Tyler Long is following:', ', '.join(user.name for user in tyler.users_i_follow)
print 'People who are following Tyler Long:', ', '.join(user.name for user in tyler.users_follow_me)
mark = db.session.query(User).filter_by(name = 'Mark Wong').one()
print 'Mark Wong is following:', ', '.join(user.name for user in mark.users_i_follow)



One-to-one relationship example
*******************************
from quick_orm.core import Database
from sqlalchemy import Column, String

class User(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(30))

@Database.one_to_one(User)
class Contact(object):
__metaclass__ = Database.DefaultMeta
email = Column(String(70))
address = Column(String(70))

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()

contact = Contact(email = '[e-mail]', address = 'Shenzhen, China')
user = User(name = 'Tyler Long', contact = contact)
db.session.add_then_commit(user)

user = db.session.query(User).get(1)
print 'User:', user.name
print 'Email:', user.contact.email
print 'Address:', user.contact.address



Multiple foreign keys example
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from quick_orm.core import Database
from sqlalchemy import Column, String, Text

class User(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(30))

@Database.foreign_key(User, ref_name = 'author', backref_name = 'articles_authored')
@Database.foreign_key(User, ref_name = 'editor', backref_name = 'articles_edited')
class Article(object):
__metaclass__ = Database.DefaultMeta
title = Column(String(80))
content = Column(Text)

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()

author = User(name = 'Tyler Long')
editor = User(name = 'Peter Lau')
article = Article(author = author, editor = editor, title = 'Quick ORM is super quick and easy',
content = 'Quick ORM is super quick and easy. Believe it or not.')
db.session.add_then_commit(article)

article = db.session.query(Article).get(1)
print 'Article:', article.title
print 'Author:', article.author.name
print 'Editor:', article.editor.name



Performing raw sql query example
********************************
from quick_orm.core import Database
from sqlalchemy import Column, String

class User(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(70))

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()

count = db.engine.execute('select count(name) from user').scalar()
print 'There are {0} users in total'.format(count)



Multiple databases example
**************************
from quick_orm.core import Database
from sqlalchemy import Column, String

class User(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(30))

if __name__ == '__main__':
db1 = Database('sqlite://')
db1.create_tables()

db2 = Database('sqlite://')
db2.create_tables()

user1 = User(name = 'user in db1')
user2 = User(name = 'user in db2')
db1.session.add_then_commit(user1)
db2.session.add_then_commit(user2)

print 'I am', db1.session.query(User).get(1).name
print 'I am', db2.session.query(User).get(1).name



Table inheritance example
*************************
from quick_orm.core import Database
from sqlalchemy import Column, String, Text

class User(object):
__metaclass__ = Database.DefaultMeta
name = Column(String(70))

@Database.foreign_key(User)
class Post(object):
__metaclass__ = Database.DefaultMeta
content = Column(Text)

class Question(Post):
title = Column(String(70))

@Database.foreign_key(Question)
class Answer(Post):
pass

@Database.foreign_key(Post)
class Comment(Post):
pass

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()

user1 = User(name = 'Tyler Long')
user2 = User(name = 'Peter Lau')

question = Question(user = user1, title = 'What is Quick ORM ?', content = 'What is Quick ORM ?')
answer = Answer(user = user1, question = question,
content = 'Quick ORM is a python ORM which enables you to get started in less than a minute!')
comment1 = Comment(user = user2, content = 'good question', post = question)
comment2 = Comment(user = user2, content = 'nice answer', post = answer)
db.session.add_all_then_commit([question, answer, comment1, comment2])

question = db.session.query(Question).get(1)
print 'new comment on question:', question.comments.first().content
print 'new comment on answer:', question.answers.first().comments.first().content

# Could the last two lines work as you expected? Try it yourself!
user = db.session.query(User).filter_by(name = 'Peter Lau').one()
print 'Peter Lau has posted {0} comments'.format(user.comments.count())



MetaBuilder to avoid dupliate code example
******************************************
from quick_orm.core import Database
from sqlalchemy import Column, String, DateTime, func

class DefaultModel(object):
name = Column(String(70))
created = Column(DateTime, default = func.now(), nullable = False)

metaclass = Database.MetaBuilder(DefaultModel)

class User(object):
__metaclass__ = metaclass

class Group(object):
__metaclass__ = metaclass

if __name__ == '__main__':
db = Database('sqlite://')
db.create_tables()
user = User(name = 'tylerlong')
db.session.add(user)
group = Group(name = 'python')
db.session.add_then_commit(group)

print user.name, user.created
print group.name, group.created



More examples
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More examples could be found in folder site-packages/quick_orm/examples/
And even more examples are being added



Where to learn more about quick_orm?
************************************
As said above, quick_orm is built upon SQLAlchemy. Quick ORM never tries to hide SQLAlchemy's flexibility and power.
Everything availiable in SQLAlchemy is still available in quick_orm.
So please read the documents of SQLAlchemy, you would learn much more there than you could here.
Read quick_orm's source code, try to improve it.



You wanna involve?
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Quick ORM is released under BSD lisence.
The source code is hosted on github: https://github.com/tylerlong/quick_orm



Acknowledgements
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Quick ORM is built upon SQLAlchemy - the famous Python SQL Toolkit and Object Relational Mapper.
All of the glory belongs to the SQLAlchemy development team and the SQLAlchemy community!
My contribution to Quich ORM becomes trivial compared with theirs( to SQLAlchemy).



Feedback
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Comments, suggestions, questions, free beer, t-shirts, kindles, ipads ... are all welcome!
Email: [e-mail]