Questions tagged [django]
Django is an open-source server-side web application framework written in Python. It is designed to reduce the effort required to create complex data-driven websites and web applications, with a special focus on less code, no-redundancy and being more explicit than implicit.
309,596
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What is the difference between null=True and blank=True in Django?
When we add a model field in Django we generally write:
models.CharField(max_length=100, null=True, blank=True)
The same is done with ForeignKey, DecimalField etc. What is the basic difference ...
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29
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Has Django served an excess of 100k daily visits? [closed]
I'm building a web application with Django. The reasons I chose Django were:
I wanted to work with free/open-source tools.
I like Python and feel it's a long-term language, whereas regarding Ruby I ...
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968
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10
answers
669k
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Is there a list of Pytz Timezones?
I would like to know what are all the possible values for the timezone argument in the Python library pytz. How to do it?
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17
answers
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How do I do a not equal in Django queryset filtering?
In Django model QuerySets, I see that there is a __gt and __lt for comparative values, but is there a __ne or != (not equals)? I want to filter out using a not equals. For example, for
Model:
bool ...
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823
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16
answers
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How to combine multiple QuerySets in Django?
I'm trying to build the search for a Django site I am building, and in that search, I am searching across three different models. And to get pagination on the search result list, I would like to use a ...
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808
votes
10
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851k
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How can I temporarily disable a foreign key constraint in MySQL?
Is it possible to temporarily disable constraints in MySQL?
I have two Django models, each with a foreign key to the other one. Deleting instances of a model returns an error because of the foreign ...
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votes
14
answers
256k
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What is a "slug" in Django?
When I read Django code I often see in models what is called a "slug". I am not quite sure what this is, but I do know it has something to do with URLs. How and when is this slug-thing ...
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756
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14
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466k
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How to revert the last migration?
I've made a migration that added a new table and want to revert it and delete the migration, without creating a new migration.
How do I do it? Is there a command to revert last migration and then I ...
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10
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How to upload a file in Django? [closed]
What is the minimal example code needed for a "hello world" app using Django 1.3, that enables the user to upload a file?
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730
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10
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Where does pip install its packages?
I activated a virtualenv which has pip installed. I did
pip3 install Django==1.8
and Django successfully downloaded. Now, I want to open up the Django folder. Where is the folder located?
Normally it ...
- 21.1k
704
votes
11
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What does on_delete do on Django models?
I'm quite familiar with Django, but I recently noticed there exists an on_delete=models.CASCADE option with the models. I have searched for the documentation for the same, but I couldn't find anything ...
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702
votes
32
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How to check Django version
I have to use Python and Django for our application. So, I have two versions of Python, 2.6 and 2.7. Now I have installed Django. I could run the sample application for testing Django succesfuly. But ...
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658
votes
6
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What is related_name used for?
What is the related_name argument useful for on ManyToManyField and ForeignKey fields? For example, given the following code, what is the effect of related_name='maps'?
class Map(db.Model):
...
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652
votes
27
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How to debug in Django, the good way? [closed]
So, I started learning to code in Python and later Django. The first times it was hard looking at tracebacks and actually figure out what I did wrong and where the syntax error was. Some time has ...
- 33.1k
640
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11
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1.2m
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How can I upgrade specific packages using pip and a requirements file?
I'm using pip with a requirements file, in a virtualenv, for my Django projects. I'm trying to upgrade some packages, notably Django itself, and I'm getting an error about source code conflicts:
...
- 6,457
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24
answers
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How to reset Django admin password?
I am using Django (version 1.3) and have forgotten both admin username and password. How to reset both?
And is it possible to make a normal user into admin, and then remove admin status?
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19
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883k
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How to get GET request values in Django?
I am currently defining regular expressions in order to capture parameters in a URL, as described in the tutorial. How do I access parameters from the URL as part the HttpRequest object?
My ...
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610
votes
9
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502k
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How to filter empty or NULL names in a QuerySet?
I have first_name, last_name & alias (optional) which I need to search for. So, I need a query to give me all the names that have an alias set.
Only if I could do:
Name.objects.filter(alias!="")
...
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609
votes
9
answers
149k
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Separation of business logic and data access in django
I am writing a project in Django and I see that 80% of the code is in the file models.py. This code is confusing and, after a certain time, I cease to understand what is really happening.
Here is what ...
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585
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26
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Set up a scheduled job?
I've been working on a web app using Django, and I'm curious if there is a way to schedule a job to run periodically.
Basically I just want to run through the database and make some calculations/...
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5
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How to define two fields "unique" as couple
Is there a way to define a couple of fields as unique in Django?
I have a table of volumes (of journals) and I don't want more then one volume number for the same journal.
class Volume(models.Model):...
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570
votes
17
answers
739k
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Creating a JSON response using Django and Python
I'm trying to convert a server side Ajax response script into a Django HttpResponse, but apparently it's not working.
This is the server-side script:
/* RECEIVE VALUE */
$validateValue=$_POST['...
- 14.8k
570
votes
38
answers
723k
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No module named pkg_resources
I'm deploying a Django app to a dev server and am hitting this error when I run pip install -r requirements.txt:
Traceback (most recent call last):
File "/var/www/mydir/virtualenvs/dev/bin/pip", ...
- 8,424
560
votes
42
answers
2.5m
views
'pip' is not recognized as an internal or external command
I'm running into a weird error when trying to install Django on my computer.
This is the sequence that I typed into my command line:
C:\Python34> python get-pip.py
Requirement already up-to-date: ...
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555
votes
12
answers
194k
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OneToOneField() vs ForeignKey() in Django
What's the difference between Django OneToOneField and ForeignKey?
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votes
17
answers
323k
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What's the best way to extend the User model in Django?
What's the best way to extend the User model (bundled with Django's authentication app) with custom fields? I would also possibly like to use the email as the username (for authentication purposes).
...
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524
votes
33
answers
924k
views
No module named MySQLdb
I am using Python version 2.5.4 and install MySQL version 5.0 and Django. Django is working fine with Python, but not MySQL. I am using it in Windows Vista.
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votes
30
answers
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In a Django form, how do I make a field readonly (or disabled) so that it cannot be edited?
In a Django form, how do I make a field read-only (or disabled)?
When the form is being used to create a new entry, all fields should be enabled - but when the record is in update mode some fields ...
- 17.2k
522
votes
6
answers
304k
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What's the difference between select_related and prefetch_related in Django ORM?
In Django doc:
select_related() "follows" foreign-key relationships, selecting additional related-object data when it executes its query.
prefetch_related() does a separate lookup for each ...
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516
votes
12
answers
368k
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RuntimeWarning: DateTimeField received a naive datetime
I m trying to send a simple mail using IPython. I have not set up any models still getting this error. What can be done?
Error :
/home/sourabh/Django/learn/local/lib/python2.7/site-packages/...
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votes
21
answers
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views
Why does DEBUG=False setting make my django Static Files Access fail?
Am building an app using Django as my workhorse. All has been well so far - specified db settings, configured static directories, urls, views etc. But trouble started sneaking in the moment I wanted ...
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499
votes
13
answers
535k
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How to query as GROUP BY in Django?
I query a model:
Members.objects.all()
And it returns:
Eric, Salesman, X-Shop
Freddie, Manager, X2-Shop
Teddy, Salesman, X2-Shop
Sean, Manager, X2-Shop
What I want is to know the best Django way ...
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498
votes
30
answers
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How can I get the full/absolute URL (with domain) in Django?
How can I get the full/absolute URL (e.g. https://example.com/some/path) in Django without the Sites module? That's just silly... I shouldn't need to query my DB to snag the URL!
I want to use it ...
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votes
12
answers
737k
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CORS: Cannot use wildcard in Access-Control-Allow-Origin when credentials flag is true
I have a setup involving
Frontend server (Node.js, domain: localhost:3000) <---> Backend (Django, Ajax, domain: localhost:8000)
Browser <-- webapp <-- Node.js (Serve the app)
Browser (...
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votes
32
answers
767k
views
How to convert JSON data into a Python object?
I want to convert JSON data into a Python object.
I receive JSON data objects from the Facebook API, which I want to store in my database.
My current View in Django (Python) (request.POST contains the ...
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votes
8
answers
285k
views
How do I do an OR filter in a Django query?
I want to be able to list the items that either a user has added (they are listed as the creator) or the item has been approved.
So I basically need to select:
item.creator = owner or item.moderated ...
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477
votes
12
answers
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django order_by query set, ascending and descending
How can I order by descending my query set in django by date?
Reserved.objects.all().filter(client=client_id).order_by('check_in')
I just want to filter from descending all the Reserved by check_in ...
- 21.7k
473
votes
10
answers
575k
views
How to delete a record in Django models?
I want to delete a particular record like:
delete from table_name where id = 1;
How can I do this in a django model?
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457
votes
18
answers
363k
views
Convert Django Model object to dict with all of the fields intact
How does one convert a django Model object to a dict with all of its fields? All ideally includes foreign keys and fields with editable=False.
Let me elaborate. Let's say I have a django model like ...
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votes
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How can I filter a Django query with a list of values?
I'm sure this is a trivial operation, but I can't figure out how it's done.
There's got to be something smarter than this:
ids = [1, 3, 6, 7, 9]
for id in ids:
MyModel.objects.filter(pk=id)
I'...
- 18.3k
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votes
25
answers
303k
views
How to see the raw SQL queries Django is running?
Is there a way to show the SQL that Django is running while performing a query?
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10
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views
Where can I find the error logs of nginx, using FastCGI and Django?
I'm using Django with FastCGI + nginx. Where are the logs (errors) stored in this case?
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17
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Can I access constants in settings.py from templates in Django?
I have some stuff in settings.py that I'd like to be able to access from a template, but I can't figure out how to do it. I already tried
{{CONSTANT_NAME}}
but that doesn't seem to work. Is this ...
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votes
16
answers
495k
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NumPy array is not JSON serializable
After creating a NumPy array, and saving it as a Django context variable, I receive the following error when loading the webpage:
array([ 0, 239, 479, 717, 952, 1192, 1432, 1667], dtype=int64) ...
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431
votes
5
answers
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Django Model() vs Model.objects.create()
What it the difference between running two commands:
foo = FooModel()
and
bar = BarModel.objects.create()
Does the second one immediately create a BarModel in the database, while for FooModel, the ...
- 13.5k
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votes
6
answers
284k
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How to perform OR condition in django queryset?
I want to write a Django query equivalent to this SQL query:
SELECT * from user where income >= 5000 or income is NULL.
How to construct the Django queryset filter?
User.objects.filter(...
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15
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243k
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Can "list_display" in a Django ModelAdmin display attributes of ForeignKey fields?
I have a Person model that has a foreign key relationship to Book, which has a number of fields, but I'm most concerned about author (a standard CharField).
With that being said, in my PersonAdmin ...
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410
votes
5
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Getting the SQL from a Django QuerySet
How do I get the SQL that Django will use on the database from a QuerySet object? I'm trying to debug some strange behavior, but I'm not sure what queries are going to the database.
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(13: Permission denied) while connecting to upstream:[nginx]
I am working with configuring Django project with Nginx and Gunicorn.
While I am accessing my port gunicorn mysite.wsgi:application --bind=127.0.0.1:8001 in Nginx server, I am getting the following ...
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5
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What's the difference between CharField and TextField in Django?
The documentation says that CharField() should be used for smaller strings and TextField() should be used for larger strings.
Okay, but where is the line drawn between "small" and "...
- 4,567