Metadata-Version: 1.0
Name: peewee
Version: 0.3.0
Summary: a little orm
Home-page: http://github.com/coleifer/peewee/
Author: Charles Leifer
Author-email: coleifer@gmail.com
License: UNKNOWN
Description: peewee
        ======
        
        * a small orm
        * written in python
        * provides a lightweight querying interface over sql
        * uses sql concepts when querying, like joins and where clauses
        
        
        Examples::
        
            # a simple query selecting a user
            User.get(username='charles')
            
            # get the staff and super users
            editors = User.select().where(Q(is_staff=True) | Q(is_superuser=True))
            
            # get tweets by editors
            Tweet.select().where(user__in=editors)
            
            # how many active users are there?
            User.select().where(active=True).count()
            
            # paginate the user table and show me page 3 (users 41-60)
            User.select().order_by(('username', 'asc')).paginate(3, 20)
            
            # order users by number of tweets
            User.select({
                User: ['*'],
                Tweet: [Count('id', 'num_tweets')]
            }).group_by('id').join(Tweet).order_by(('num_tweets', 'desc'))
        
        
        Why?
        ----
        
        peewee began when I was working on a small app in flask and found myself writing
        lots of queries and wanting a very simple abstraction on top of the sql.  I had
        so much fun working on it that I kept adding features.  My goal has always been,
        though, to keep the implementation incredibly simple.  I've made a couple dives
        into django's orm but have never come away with a deep understanding of its
        implementation.  peewee is small enough that its my hope anyone with an interest
        in orms will be able to understand the code without too much trouble.
        
        
        model definitions and schema creation
        -------------------------------------
        
        smells like django::
        
        
            import peewee
            
            class Blog(peewee.Model):
                title = peewee.CharField()
                
                def __unicode__(self):
                    return self.title
            
            class Entry(peewee.Model):
                title = peewee.CharField(max_length=50)
                content = peewee.TextField()
                pub_date = peewee.DateTimeField()
                blog = peewee.ForeignKeyField(Blog)
        
                def __unicode__(self):
                    return '%s: %s' % (self.blog.title, self.title)
        
        
        gotta connect::
        
            >>> from peewee import database
            >>> database.connect()
        
        create some tables::
        
            >>> Blog.create_table()
            >>> Entry.create_table()
        
        
        foreign keys work like django's
        -------------------------------
        
            >>> b = Blog(title="Peewee's Big Adventure")
            >>> b.save()
            >>> e = Entry(title="Greatest movie ever?", content="YES!", blog=b)
            >>> e.save()
            >>> e.blog
            <Blog: Peewee's Big Adventure>
            >>> for e in b.entry_set:
            ...     print e.title
            ... 
            Greatest movie ever?
        
        
        querying
        --------
        
        queries come in 4 flavors (select/update/insert/delete).
        
        there's the notion of a *query context* which is the model being selected
        or joined on::
        
            User.select().where(active=True).order_by(('username', 'asc'))
        
        since User is the model being selected, the where clause and the order_by will
        pertain to attributes on the User model.  User is the current query context
        when the .where() and .order_by() are evaluated.
        
        an example using joins::
        
            Tweet.select().where(deleted=False).order_by(('pub_date', 'desc')).join(
                User
            ).where(active=True)
        
        this will select non-deleted tweets from active users.  the first .where() and
        .order_by() occur when Tweet is the current *query context*.  As soon as the
        join is evaluated, User becomes the *query context* and so the following
        where() pertains to the User model.
        
        
        now with q objects
        ------------------
        
        for users familiar with django's orm, I've implemented OR queries and complex
        query nesting using similar notation::
        
            User.select().where(
                Q(is_superuser = True) |
                Q(is_staff = True)
            )
        
            SomeModel.select().where(
                (Q(a='A') | Q(b='B')) &
                (Q(c='C') | Q(d='D'))
            )
        
            # generates something like:
            # SELECT * FROM some_obj 
            # WHERE ((a = "A" OR b = "B") AND (c = "C" OR d = "D"))
        
Platform: UNKNOWN
Classifier: Development Status :: 4 - Beta
Classifier: Environment :: Web Environment
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: MIT License
Classifier: Operating System :: OS Independent
Classifier: Programming Language :: Python
