一个小型ORM
项目描述
peewee
Peewee是一个简单小巧的ORM。它具有少量（但表达性强）的概念，使其易于学习和使用。
一个小型、表达性强的ORM
python 2.7+ 和 3.4+
支持sqlite、mysql、mariadb、postgresql和cockroachdb
众多 扩展
新接触peewee？以下内容可能有所帮助
示例
定义模型类似于Django或SQLAlchemy
from peewee import *
import datetime
db = SqliteDatabase('my_database.db')
class BaseModel(Model):
class Meta:
database = db
class User(BaseModel):
username = CharField(unique=True)
class Tweet(BaseModel):
user = ForeignKeyField(User, backref='tweets')
message = TextField()
created_date = DateTimeField(default=datetime.datetime.now)
is_published = BooleanField(default=True)连接到数据库并创建表
db.connect()
db.create_tables([User, Tweet])创建几行
charlie = User.create(username='charlie')
huey = User(username='huey')
huey.save()
# No need to set `is_published` or `created_date` since they
# will just use the default values we specified.
Tweet.create(user=charlie, message='My first tweet')查询表达性强且可组合
# A simple query selecting a user.
User.get(User.username == 'charlie')
# Get tweets created by one of several users.
usernames = ['charlie', 'huey', 'mickey']
users = User.select().where(User.username.in_(usernames))
tweets = Tweet.select().where(Tweet.user.in_(users))
# We could accomplish the same using a JOIN:
tweets = (Tweet
.select()
.join(User)
.where(User.username.in_(usernames)))
# How many tweets were published today?
tweets_today = (Tweet
.select()
.where(
(Tweet.created_date >= datetime.date.today()) &
(Tweet.is_published == True))
.count())
# Paginate the user table and show me page 3 (users 41-60).
User.select().order_by(User.username).paginate(3, 20)
# Order users by the number of tweets they've created:
tweet_ct = fn.Count(Tweet.id)
users = (User
.select(User, tweet_ct.alias('ct'))
.join(Tweet, JOIN.LEFT_OUTER)
.group_by(User)
.order_by(tweet_ct.desc()))
# Do an atomic update (for illustrative purposes only, imagine a simple
# table for tracking a "count" associated with each URL). We don't want to
# naively get the save in two separate steps since this is prone to race
# conditions.
Counter.update(count=Counter.count + 1).where(Counter.url == request.url)查看 示例Twitter应用。
了解更多
查看 文档 以获取更多示例。
有特定问题？加入irc.libera.chat上的#peewee频道，或在邮件列表 http://groups.google.com/group/peewee-orm 上发帖。如果您想报告一个错误，请在GitHub上 创建一个新问题。
还想了解更多信息吗？
我写了一些关于使用 peewee（通常与 Flask 一起）构建应用程序和 web 服务器的博客文章。如果你想看看使用 peewee 的真实应用，以下资源可能对你有帮助
