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    <p>Add a <a href="https://docs.djangoproject.com/en/1.4/ref/models/fields/#django.db.models.ForeignKey.related_name" rel="nofollow"><code>related_name</code></a> to the foreign key, then use the <a href="https://docs.djangoproject.com/en/1.4/ref/models/querysets/#prefetch-related" rel="nofollow"><code>prefetch_related</code></a> method which added to Django 1.4:</p> <blockquote> <p>Returns a <code>QuerySet</code> that will automatically retrieve, in a single batch, related objects for each of the specified lookups.</p> <p>This has a similar purpose to <code>select_related</code>, in that both are designed to stop the deluge of database queries that is caused by accessing related objects, but the strategy is quite different:</p> <ul> <li><p><code>select_related</code> works by creating a SQL join and including the fields of the related object in the <code>SELECT</code> statement. For this reason, <code>select_related</code> gets the related objects in the same database query. However, to avoid the much larger result set that would result from joining across a 'many' relationship, <code>select_related</code> is limited to single-valued relationships - foreign key and one-to-one.</p></li> <li><p><code>prefetch_related</code>, on the other hand, does a separate lookup for each relationship, and does the 'joining' in Python. This allows it to prefetch many-to-many and <strong>many-to-one objects</strong>, which cannot be done using <code>select_related</code>, in addition to the foreign key and one-to-one relationships that are supported by <code>select_related</code>. It also supports prefetching of <code>GenericRelation</code> and <code>GenericForeignKey</code>.</p></li> </ul> </blockquote> <pre><code>class Parent(models.Model): name = models.CharField(max_length=31) class Child(models.Model): name = models.CharField(max_length=31) parent = models.ForeignKey(Parent, related_name='children') &gt;&gt;&gt; Parent.objects.all().prefetch_related('children') </code></pre> <p>All the relevant children will be fetched in a single query, and used to make QuerySets that have a pre-filled cache of the relevant results. These QuerySets are then used in the <code>self.children.all()</code> calls.</p> <blockquote> <p><strong>Note 1</strong> that, as always with QuerySets, any subsequent chained methods which imply a different database query will ignore previously cached results, and retrieve data using a fresh database query.</p> <p><strong>Note 2</strong> that if you use <code>iterator()</code> to run the query, <code>prefetch_related()</code> calls will be ignored since these two optimizations do not make sense together.</p> </blockquote>
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    1. POList of parents objects and their children with fewer queries
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    1. POList of parents objects and their children with fewer queries
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    1. COI've read the Django docs you're quoting there. While `prefetch_related` seems to do what I'm after, applying it to my query didn't change the number of queries - perhaps I'm doing it wrong... Could you provide an example call?
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    2. COJust checked in my project similar case - is executed exactly 2 request. Most likely the problem is, how do you select children from their parents. You can not use `filter` method. This leads to a new request. Use `parent.children.all()`
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    3. COAlso, from doc: Note that if you use `iterator()` to run the query, `prefetch_related()` calls will be ignored since these two optimizations do not make sense together.
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Guidance
A row detail

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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