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Date: Thu, 8 May 2008 09:17:08 -0700 (PDT)
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Subject: Re: Many-to-many JOIN with the Datastore
From: "arbinger...@gmail.com" <arbinger...@gmail.com>
To: Google App Engine <google-appengine@googlegroups.com>
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On May 3, 2:27 pm, cyj <chenyue...@gmail.com> wrote:
> Hi, I am a newbie to both GAE and python.
> I have a question about how to query the m:n model simulated by GAE?
> e.g. get a library has book1.

That's described in this post:

http://blog.arbingersys.com/2008/04/google-app-engine-better-many-to-many.html

Specifically, I pass

'libs_by_book': book1.libraries(),

to the template, which in turn does:

  <h4>All libraries with book "{{ forbook }}"</h4>
  <table border="1">
      {% for lib in libs_by_book %}
        <tr>
            <td>{{ lib.name }}</td>
            <td>{{ lib.address }}</td>
            <td>{{ lib.city }}</td>
        </tr>
        {% endfor %}