Here is my solution (based on a custom tag): Firstly create the file structure. Go into the app directory where the tag is needed, and add these files: templatetags templatetags/__init__.py templatetags/video_tags.py The templatetags/video_tags.py file: from django import template register = template.Library() @register.simple_tag def get_rate(crit, rates): return rates.get(crit=crit).rate The template part, with our tag call: {% … Read more
Finally got it to work, although I don’t know why and I hope it will work in the future. After doing numerous trials and going through Django’s dev site (link). Here are the steps (for whoever runs into this problem): Empty the django_migrations table: delete from django_migrations; For every app, delete its migrations folder: rm … Read more
You’re not going to. M2Ms are saved after instances are saved and thus there won’t be any record at all of the m2m updates. Further issues (even if you solve that) are that you’re still in a transaction and querying the DB won’t get you m2m with proper states anyways. The solution is to hook … Read more
The way I understand it is that they are subtly different by design (and I am certainly open for correction): filter(A, B) will first filter according to A and then subfilter according to B, while filter(A).filter(B) will return a row that matches A ‘and’ a potentially different row that matches B. Look at the example … Read more
There is no clean way to do this with the built-in tags. Trying to do something like: {{ a.’Restaurant Name’}} or {{ a.Restaurant Name }} will throw a parse error. You could do a for loop through the dictionary (but it’s ugly/inefficient): {% for k, v in your_dict_passed_into_context %} {% ifequal k “Restaurant Name” %} … Read more
For some reason, the file is missing on the system. As you’re using apt-get, the system is dpkg based, presumably Debian or it’s derivative. You can try the Ubuntu’s package search to get which package contains a file with name ending in libpq-fe.h. I found the package is libpq-dev and file’s absolute path is /usr/include/postgresql/libpq-fe.h. … Read more
I think you can achieve this by overriding the __init__() method of the form, passing in an instance of User and filtering the queryset using that user. Something like this: class TrophiesForm(ModelForm): used_his = forms.ModelMultipleChoiceField(queryset=Gun.objects.filter(user__id=1)) def __init__(self, user, *args, **kwargs): super(TrophiesForm, self).__init__(*args, **kwargs) self.fields[‘used_his’].queryset = User.objects.filter(pk = user.id) In your view you can pass in … Read more
First, you’ll need to clear the relationship(s) by using .clear() or .remove(), whichever suits your needs better according to the docs. After that, you’ll need to delete the object(s) by using the [YourModel].delete() method.
This is exactly what select_related() does. The only gotcha is that you have to start with the Answer model, rather than Question, but the result is the same: answers = Answer.objects.filter(question_id=1).select_related() Now each answer object has a pre-fetched ‘question’ attribute, and accessing it won’t hit the db again.
If you want to achieve this within the admin interface, you can use the save_model method. See below an example: class List(models.Model): title = models.CharField(max_length=64) author = models.ForeignKey(User) class ListAdmin(admin.ModelAdmin): fields = (‘title’,) def save_model(self, request, obj, form, change): obj.author = request.user obj.save()