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  1. PO
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    <p>While your posted solution "works", it's a very PHP way of doing things.</p> <p>A more Django way:</p> <p>In your application's models.py file:</p> <pre><code>from django.db import models class Word(models.Model): word = models.CharField(max_length=60, blank=False, null=False, unique=True) def __unicode__(self): return u'%s' % self.word class RandomWordString(models.Model): string = models.CharField(max_length=255, blank=False, null=False, unique=True) def __unicode__(self): return u'%s' % self.string @staticmethod def generate(length): words = Word.objects.order_by('?')[:(length + 1)] possible_word_string = '-'.join(words.values_list('word', flat=True)) try: RandomWordString.objects.get(string=possible_word_string) # See if we've already generated this sequence return RandomWordString.generate(length) # Call ourselves again if we have except RandomWordString.DoesNotExist: return possible_word_string # If we haven't, return the value def save(self, *args, **kwargs): if not self.string or len(self.string) &lt; 1: self.string = RandomWordString.generate(3) super(RandomWordString, self).save(*args, **kwargs) </code></pre> <p>Then, from any view, or anywhere else:</p> <pre><code>from words.models import RandomWordString seq = RandomWordString.generate(3) </code></pre> <p>Because we overrode save, we can also just do:</p> <pre><code>from words.models import RandomWordString string = RandomWordString.objects.create() string.save() </code></pre> <p>This places all the logic within the models themselves, which is <em>slightly</em> better than having it in a view (though it's completely a matter of taste).</p> <p>Beyond what I've posted, you'd also want to add some logic to RandomWordString.generate to make sure you don't loop indefinitely.</p>
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    1. POCombining queryset into single string with Django
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    1. USJack Shedd
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    1. COIn my opinion you are right that it's better to have logic within models however you have you should not overuse it. One of the principles of databases is not to store duplicate data which you can easily generate unless you have a very good reason. In this case it is trivial to generate the wanted string hence the logic better fits within a view instead of models. Additionally storing the generated string in up brings a whole bunch of issues like what happens when a Word is updates. Do all string which use it should get updated?
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      1. USmiki725
    2. COI'm not storing links between the WordList and the Word, as that would be crazy (though I guess you could do it).
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      1. USJack Shedd
    3. COIn this case, it is going into the database immediately. There's a separate table that keeps track of the generated strings and some other information that is supplied by the user. There's no concern with it duplicating data or dealing with changing words. Very simple little project, rebuilding something I did in PHP to learn a bit more of Django. I get the feeling that this should go in the Model since it mainly interacts with the database.
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      1. USsubvertallchris
 

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