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    <p>Looking at the IDs, it seems that when you assign an entry to a variable, you get its copy, not its original reference:</p> <pre><code>In [11]: people = People.objects.filter(salary=100) In [12]: person = people[0] In [13]: person.salary = 5000 In [14]: print person.salary 5000 In [15]: people[0].salary Out[15]: 100 In [16]: id(people[0]) Out[16]: 35312400 In [17]: id(person) Out[17]: 35313104 </code></pre> <p>So, let's look at what it happens in depth. You know that in Django QuerySets are evaluated only when you need their results (lazy evaluation). To quote <a href="https://docs.djangoproject.com/en/dev/ref/models/querysets/#when-querysets-are-evaluated" rel="nofollow">the Django documentation</a>:</p> <blockquote> <p><strong>Slicing</strong>. As explained in Limiting QuerySets, a QuerySet can be sliced, using Python’s array-slicing syntax. Slicing an unevaluated QuerySet usually returns another unevaluated QuerySet, but Django will execute the database query if you use the “step” parameter of slice syntax, and will return a list. Slicing a QuerySet that has been evaluated (partially or fully) also returns a list.</p> </blockquote> <p>In particular, looking at the <a href="https://github.com/django/django/blob/master/django/db/models/query.py" rel="nofollow">'django.db.models.query' source code</a>,</p> <pre><code> def __getitem__(self, k): """ Retrieves an item or slice from the set of results. """ # some stuff here ... if isinstance(k, slice): qs = self._clone() if k.start is not None: start = int(k.start) else: start = None if k.stop is not None: stop = int(k.stop) else: stop = None qs.query.set_limits(start, stop) return k.step and list(qs)[::k.step] or qs qs = self._clone() qs.query.set_limits(k, k + 1) return list(qs)[0] </code></pre> <p>you can see that when you use <em>slicing</em>, you are calling the <code>__getitem__</code> method. Then the <code>self._clone</code> method will provide you a different instance of the same QuerySet. This is the reason you are getting different results.</p>
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    1. POHow can I manually modify models retrieved from the database in Django?
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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