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copied!<p>It seems that you can just use the attributes directly instead of using the <code>columns</code> <code>dict</code>.</p> <p>Consider the following setup:</p> <pre><code>from sqlalchemy import Table, Column, Integer, Unicode, MetaData, create_engine from sqlalchemy.orm import mapper, create_session class Word(object): pass wordColumns = ['english', 'korean', 'romanian'] e = create_engine('sqlite://') metadata = MetaData(bind=e) t = Table('words', metadata, Column('id', Integer, primary_key=True), *(Column(wordCol, Unicode(255)) for wordCol in wordColumns)) metadata.create_all() mapper(Word, t) session = create_session(bind=e, autocommit=False, autoflush=True) </code></pre> <p>With that empty class you can do:</p> <pre><code>w = Word() w.english = u'name' w.korean = u'이름' w.romanian = u'nume' session.add(w) session.commit() </code></pre> <p>And when you want to access the data:</p> <pre><code>w = session.query(Word).filter_by(english=u'name').one() print w.romanian </code></pre> <p>That's the <strong>whole <code>sqlalchemy</code>'s ORM point</strong>, instead of using a <code>tuple</code> or <code>dict</code> to access the data, you use <em>attribute-like</em> access on your own class.</p> <p>So I was wondering for reasons you'd like to use a <code>dict</code>. Perhaps it's because you have strings with the language names. Well, for that you could use python's <code>getattr</code> and <code>setattr</code> instead, as you would on any python object:</p> <pre><code>language = 'korean' print getattr(w, language) </code></pre> <p>That should solve all of your issues.</p> <hr> <p>That said, if you still want to use <code>dict</code>-like access to the columns, it is also possible. You just have to implement a <code>dict</code>-like object. I will now provide code to do this, even though I think it's absolutely unnecessary clutter, since attribute access is so clean. If your issue is already solved by using the method above, don't use the code below this point.</p> <p>You could do it on the <code>Word</code> class:</p> <pre><code>class Word(object): def __getitem__(self, item): return getattr(self, item) def __setitem__(self, item, value): return setattr(self, item, value) </code></pre> <p>The rest of the setup works as above. Then you could use it like this:</p> <pre><code>w = Word() w['english'] = u'name' </code></pre> <p>If you want a <code>columns</code> attribute then you need a <code>dict</code>-like </p> <pre><code>class AttributeDict(DictMixin): def __init__(self, obj): self._obj = obj def __getitem__(self, item): return getattr(self._obj, item) def __setitem__(self, item, value): return setattr(self._obj, item, value) class Word(object): def __init__(self): self.columns = AttributeDict(self) </code></pre> <p>Then you could use as you intended:</p> <pre><code>w = Word() w.columns['english'] = u'name' </code></pre> <p>I think you'll agree that all this is unnecessarly complicated with no added benefit.</p>

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