I'm struggling getting my head around the Django's ORM. What I want to do is get a list of distinct values within a field on my table .... the equivalent of one of the following: SELECT DISTINCT myfieldname FROM mytable (or alternatively) SELECT myfieldname FROM mytable GROUP BY myfieldname I'd at least like to do it the Django way...
Hope this makes sense... Is there a simple way to return a set of values from a table based on a single column's values being distinctly unique? What I'm hoping for is something like: SegCode.query.filter(ref.unique()).only('ref') That's not real code, but I was hoping there was some simple function out there that will accomplish thi...
Hello All: I am hoping someone can help me out with a quick question I have regarding chaining Django querysets. I am noticing a slow down because I am evaluating many data points in the database to create data trends. I was wondering if there was a way to have the chained filters evaluated locally instead of hitting the database. He...
Like in this question, except I want to be able to have querysets that return a mixed body of objects: >>> Product.objects.all() [<SimpleProduct: ...>, <OtherProduct: ...>, <BlueProduct: ...>, ...] I figured out that I can't just set Product.Meta.abstract to true or otherwise just OR together querysets of differing objects. Fine, but...
There are database string values that are sometimes stored with unnecessary spaces: "SDF@#$#@ 132423" Given the value without spaces in the UI of a program: "SDF@#$#@132423" How could I do a Django queryset filter to find the Database value (with spaces) from the UI input value sans spaces? ...
I cannot run ['abc'].append( MyModel.objects.all() ) since it generates exception 'NoneType' object is not iterable if MyModel has no entry. any workaround or something like ? : in c++ edit: my statement is actually ','.join([ str(e) for e in ['abc','def'].append( MyModel.objects.all() ) ]) it seems that the problem is caused by ...
This is just an example, but given the following model: class Foo(models.model): bar = models.IntegerField() def __str__(self): return str(self.bar) def __unicode__(self): return str(self.bar) And the following QuerySet object: foobar = Foo.objects.filter(bar__lt=20).distinct() (meaning, a set of uniq...
Let's say I have a site where Users can add Entries through admin panel. Each User has his own Category he is responsible for (each Category has an Editor assigned through ForeingKey/ManyToManyField). When User adds Entry, I limit the choices by using EntryAdmin like this: class EntryAdmin(admin.ModelAdmin): (...) def formfiel...
This question is connected to my other question but I changed the logic a bit. I have models like this: from django.contrib.auth.models import Group class Category(models.Model): (...) editors = ForeignKey(Group) class Entry(models.Model): (...) category = ForeignKey(Category) Now let's say User logs into admin panel an...
I have model with a Foreign Key to itself like this: class Concept(models.Model): name = models.CharField(max_length=200) category = models.ForeignKey('self') But I can't figure out how I can select all concepts that have nonzero children value. Is this possible with django QuerySet API or I must write custom SQL? ...
Hi, I have a list of names that I want to match case insensitive, is there a way to do it without using a loop like below? a = ['name1', 'name2', 'name3'] result = any([Name.objects.filter(name__iexact=name) for name in a]) ...
I'm using the extra() modifier in a view. (See http://docs.djangoproject.com/en/1.1/ref/models/querysets/#extra-select-none-where-none-params-none-tables-none-order-by-none-select-params-none ) Here's the the code: def viewname(request) ... exact_matchstrings=[] exact_matchstrings.append("(accountprofile.first_name LIKE '"...
I need to amend QuerySet data when i return it to a template. for example, model.objects.all() returns a date (with other fields), but i also want to return the number of days since that date has passed. This is so that in the template, i can say "you last logged in 4 days ago". What is the best way to do this? ...
In Django 1.1 I was able to produce the SQL used by a QuerySet with this notation: QuerySet.query.as_sql() In Django 1.2, this raises as AttributeError. Anyone know the Django 1.2 equivalent of that method? Thanks ...
I need order a Queryset by date in desc order, but i need put in the end the objects at the end, I do this: qs1 = Model.objects.exclude(date=None).order_by('-date') qs2 = Model.objects.filter(date=None).order_by('-date') and my list is: l = list(qs1)+list(qs2) There is a more efficiently way for this? ...
How can i use order_by like order_by('field1'*'field2') For example i have items with price listed in different currencies, so to order items - i have to make currency conversion. class Currency(models.Model): code = models.CharField(max_length=3, primary_key=True) rateToUSD = models.DecimalField(max_digits=20,decimal_pla...
Is there a simple way to discard/remove the last result in a queryset without affecting the db? I am trying to paginate results in Django, but don't know the total number of objects for a given query. I was planning on using next/previous or older/newer links, so I only need to know if this is the first and/or last page. First is easy...
Hi, I am using the filter icontains to search for words but I only want it to match whole words. e.g. if I searched for liver I wouldn't want it returning delivery. my query looks like this MyModel.objects.filter(title__icontains=search_word) I have seen the filter __search but this does not bring back results with 3 characters or l...
Hi folks, I'm finding this a bit tricky! Maybe someone can help me on this one I have the following model: class Unicorn(models.Model): horn_length = models.IntegerField() skin_color = models.CharField() average_speed = models.IntegerField() magical = models.BooleanField() affinity = models.CharField() I would like to sea...
Hi folks, is there any way of doing the following Unicorn.objects.or_filter(magical=True).or_filter(unicorn_length=15).or_filter(skin_color='White').or_filter(skin_color='Blue') where or_filter stands for an isolated match I remember using something similar but cannot find the function anymore! Help would be great! Thanks :) ...