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  1. PO
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    <p>What you want to use is <a href="http://docs.python.org/2/library/itertools.html#itertools.chain.from_iterable" rel="nofollow">chain.from_iterable</a>. This will prevent the queries from being run more than once.</p> <pre><code>gallery_list = tuple(chain.from_iterable(grade_pk_categories,grade_pk_galleries,grade_k_categories,grade_k_galleries,grade_1_categories,grade_1_galleries,grade_2_categories,grade_2_galleries,grade_3_categories,grade_3_galleries,grade_4_categories,grade_4_galleries,grade_5_categories,grade_5_galleries,grade_6_categories,grade_6_galleries,grade_7_categories,grade_7_galleries,grade_8_categories,grade_8_galleries)) </code></pre> <p>You also want to be sorting after you run your items through a <code>set</code>, not before.</p> <pre><code>gallery_list = list(sorted(frozenset(gallery_list), key=attrgetter('display_order'))) </code></pre> <p>I would reconsider how you are going about fetching all of this data. You are doing two query for each grade level when you could probably replace it with one or two queries for all of the data. </p> <p>At the very least you could use a <code>for loop</code> to reduce the amount of code you have:</p> <pre><code>grade_titles = ['pre-k', 'k', '1', '2', '3', '4', '5', '6', '7', '8'] gallery_list = [] for grade_title in grade_titles: grade = GradeLevel.objects.prefetch_related().get(title=grade_title) grade_categories = grade_pk.grade_cats.filter(active=True,featured=True) grade_galleries = grade_pk.grade_curriculum.filter(active=True,featured=True) gallery_list.extend(grade_categories) gallery_list.extend(grade_galleries) gallery_list = list(sorted(frozenset(gallery_list), key=attrgetter('display_order'))) </code></pre>
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    1. PODjango Query Optimization - Using Itertools
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    1. USNathan Villaescusa
    1. USNathan Villaescusa
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    1. COThanks for the quick response. Let me give this a shot.
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      1. USLeachy Peachy
    2. COBTW, you can also add `.all()` to the end of a query to fetch it immediately.
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      1. USNathan Villaescusa
 

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