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PODjango ManyToMany 'str' object has no attribute
 

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  1. PODjango ManyToMany 'str' object has no attribute
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    <p>I am having an issue with what appears Django using the string name and not getting the "object" associated with that name. I'm trying to use a ManyToMany relationship, but I can't quite figure it out. The error I am getting is:</p> <pre><code>AttributeError at &lt;URL&gt; 'str' object has no attribute '_default_manager' </code></pre> <p>Here's my model setup:</p> <p><strong>models/hood.py</strong></p> <pre><code>class Hood(models.Model): name = models.CharField(unique=True) restaurants=models.ManyToManyField(Restaurant, through="restaurant_hood_map.RestaurantHoodMap") class Meta: db_table = "hoods" app_label="delivery" </code></pre> <p><strong>models/restaurant.py</strong></p> <pre><code>class Restaurant(models.model): name=models.ForeignKey(CompanyName) is_active=models.BooleanField(default=True) class Meta: db_table="restaurants" app_label="delivery" </code></pre> <p><strong>models/restuarant_hood_map.py</strong></p> <pre><code>&lt;import restaurant and hood&gt; class RestaurantHoodMap(models.Model): restaurant = models.ForeignKey(Restaurant) hood = models.ForeignKey(Hood) class Meta: db_table="restaurant_hood_map" app_label="delivery" </code></pre> <p>Now, I know what the problem is.....when I attempt to get the related restaurants off of Hood, I am getting this error. That's because it's treating the "restaurant.Restaurant" as a string value. However, I thought it was accepted to use string values in order to avoid circular dependencies? At least thats what I thought from the docs:</p> <p><a href="https://docs.djangoproject.com/en/dev/ref/models/fields/#foreignkey" rel="nofollow noreferrer">https://docs.djangoproject.com/en/dev/ref/models/fields/#foreignkey</a></p> <p>I also followed this example, which looked like exactly what I wanted:</p> <p><a href="https://stackoverflow.com/questions/4907913/how-do-i-tell-django-to-not-create-a-table-for-an-m2m-related-field">How do I tell Django to not create a table for an M2M related field?</a></p> <p>However, that doesn't seem to work when you get a Hood object and do hood.restaurants....it barfs.</p> <p>Any help would be AWESOME!</p> <p><strong>UPDATE:</strong> I made a slight change to the models to more accurately show what's happening.</p>
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    1. USJamesD
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    1. COwhere are you querying the models? Can you post the views.py or where ever you are doing queries?
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      1. USTimmy O'Mahony
 

Querying!

 
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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