My models:
class customer(models.Model):
cstid = models.AutoField(primary_key=True, unique=True)
insurance_number = models.CharField(max_length=100, blank=True, null=True)
name = models.CharField(max_length=35)
ageyrs = models.IntegerField(blank=True)
class Admission(models.Model):
id = models.AutoField(primary_key=True, unique=True)
clinic = models.ForeignKey(Clinic, on_delete=models.CASCADE)
customer = models.ForeignKey(customer, on_delete=models.CASCADE)
diagnosis = models.CharField(max_length=2000, default='', blank=True)
date_admission = models.DateTimeField(default=timezone.now)
ward = models.ForeignKey(Ward, on_delete=models.CASCADE)
bed = models.ForeignKey(Bed, on_delete=models.CASCADE)
discharged = models.BooleanField(default=False)
ip_number = models.IntegerField(blank=True)
ip_prefix = models.CharField(max_length=20, default='', blank=True)
My objective: Set a variable to a query filter, adding a property, 'is_admitted' to the queryset, so that I can pass this query set to the template and use the property while displaying data.
Code:
def is_admitted(cust):
admission = Admission.objects.filter(customer=cust, discharged=False)
admission_results = len(admission)
if admission_results > 0:
return True
return False
my_q = or_q_if_truthfull(
cstid=HospitalID,
name__lower__contains=name.lower() if name else None,
ageyrs=ageyrs if ageyrs.isdigit() else None,
agemnths=agemnths if agemnths.isdigit() else None,
mobile__contains=mobile if mobile else None,
alternate__contains=alternate if alternate else None,
email__lower__contains=email.lower() if email else None,
address__lower__contains=address.lower() if address else None,
city__lower__contains=city.lower() if city else None
)
ORSearchResult = customer.objects.filter(my_q, linkedclinic=clinicobj)
cust_set = []
cust_admission_status = []
for cust in ORSearchResult:
cust_set.append(cust)
cust_admission_status.append(is_admitted(cust))
print(f"Customer name: {cust.name} Admission status: {is_admitted(cust)}")
cust_templ_set = zip(cust_set, cust_admission_status)
And in template, I will do:
{% for cust, status in cust_templ_set %}
{{ cust.name }} {{ status }}
{% endfor %}
I want to understand how I can convert my above code by generating an aggregate over the queryset, so that I can use a property of the query, and change the template code to the following, and avoid the loop in the view, and the zip. So that the template code becomes:
{% for cust in customers %}
{{ cust.name }} {{ cust.is_admitted }}
{% endfor %}
I am not sure whether I am making complete sense, and can explain further.
I'm not sure I understood you right, perhaps you might want this:
cust = customer.objects.filter(my_q, linkedclinic=clinicobj)
is_admitted_sub_q = Admission.objects.filter(customer=OuterRef('pk'), discharged=False)
cust_templ_set = cust.annotate(is_admitted=Exists(is_admitted_sub_q), )
this will return a list of customers with additional field is_admitted which will be True if there exists at least one linked (to this customer) record in Admission.
OuterRef, Exists
One option could be to use conditional-expressions together with annotate(). It could look like this:
from django.db import models
qs = Customer.objects.filter(...) # your filter conditions go here
# now add a field to the resulting queryset
qs = qs.annotate(
active_admissions=models.Count(
models.Case(
models.When(admission__discharged=False, then=1),
output_field=models.IntegerField())))
Now each object in the queryset will have an additional attribute called active_admissions which will contain the number of active admissions.
This could be used in the template like this:
{% for cust in qs %}
{{ cust.name }} {{ cust.active_admissions }}
{% endfor %}
Maybe you need to modify the subquery to fit your specific needs. Does that help?
Related
I have a Ingredient model and a Shopping model for a shopping list and I would like to group ingredients by their category in the shopping list view. Is there a database method to achieve this or will running the for loop I have in my Views.py the easiest?
The below image is exactly what I would like to achieve in my shopping list view:
html:
{% for key, value_list in shoppingList.items %}
<div class="fw-bold">{{key}}</div>
{% for value in value_list %}
<div>
<li>{{value}}</li>
</div>
{% endfor %}
{% endfor %}
models.py:
class Ingredient(models.Model):
name = models.CharField(max_length=220)
category = models.CharField(max_length=50, default="uncategorised")
class Shopping(models.Model):
user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
name = models.CharField(max_length=220, blank=True, null=True) # users can create their own items not just those in the Ingredient model
category = models.CharField(max_length=80, default="uncategorised")
views.py:
def shopping_list_view(request):
queryset = Shopping.objects.filter(user=request.user)
shoppingList = {}
for item in queryset:
ingredientItem = item.name # e.g Fish
ingredientCategory = item.category # e.g. Meat & Seafood
if ingredientCategory in shoppingList:
shoppingLists[ingredientCategory].append(ingredientItem)
else:
shoppingLists[ingredientCategory] = []
shoppingLists[ingredientCategory].append(ingredientItem)
# print(shoppingLists)
# will return something like > {'Meat & Seafood': ['bacon', 'fish'], 'Baking & Spices': ['all purpose flour', 'parsley'], 'pantry': ['pasta']}
return render(request, "shopping/shoppinglist.html", {"shoppingList": shoppingList}
)
In case you use PostgreSQL, you can use ArrayAgg in annotate with values:
from django.contrib.postgres.aggregates import ArrayAgg
queryset = Shopping.objects.filter(
user=request.user
).values("ingredients__category").annotate(
ingredient_list=ArrayAgg('ingredients__name')
).all()
Then you'll get the list with desired structure and wouldn't need to perform any calculations at Python's side.
When I enter my user profile page, I want it to see the total number of orders until today. i tried aggregate and annonate but it's not work. I hope so i use filter method but i don't know how to do it.
Orders count = adet in model
I added ""if siparis.bayi_id == user.id"" so that the user entering can take action on his orders.
Temp Html
{% for siparis in siparis %}
{% if siparis.bayi_id == user.id %}
<strong>{{ a }}</strong><br><small>Siparişler Toplamı</small>
{% endif %}
{% endfor %}
Model Siparis means order
class Siparis(models.Model):
bayi = models.ForeignKey('auth.User', verbose_name='bayi', on_delete=models.CASCADE, related_name='bayi',limit_choices_to={'groups__name': "BayiGrubu"})
urun = models.ForeignKey(Urun, on_delete=models.CASCADE)
adet = models.IntegerField()
tarih = models.DateTimeField()
status = models.BooleanField()
#property
def miktar(self):
return (self.adet * self.urun.fiyat)
#property
def fiyat(self):
return self.urun.fiyat
class Meta:
verbose_name = 'Bayi Sipariş'
verbose_name_plural = 'Bayi Siparişleri'
views
def bayi_bayidetay(request):
siparis = Siparis.objects.all()
urunler = Urun.objects.all()
bayiler = bayi_bilgi.objects.all()
a = Siparis.objects.aggregate(Sum("adet"))
return render(request,'bayi/bayi_detay.html',{'bayiler':bayiler,'siparis':siparis,'urunler':urunler, 'a': a})
Thank you
You can try add filter after a, like this:
a = Siparis.objects.filter(bayi=request.user).aggregate(Sum("adet"))
I have such models
class Employee(models.Model):
"""Employee information."""
user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name='employee', unique=True)
position = models.CharField("current position in a company", max_length=64, blank=True)
birth_date = models.DateField("date of birth", null=True)
skills = models.ManyToManyField(
Technology, through="Skill", verbose_name="skills", blank=True)
class Technology(models.Model):
"""Technologies."""
name = models.CharField('technology name', max_length=32, unique=True)
class Skill(models.Model):
"""Information about an employee's skills."""
LEVELS = (
('basic', 'Basic'),
('intermediate', 'Intermediate'),
('advanced', 'Advanced'),
('expert', 'Expert'),
)
employee = models.ForeignKey(
Employee, on_delete=models.CASCADE, related_name="employee_skills")
technology = models.ForeignKey(Technology, on_delete=models.CASCADE)
start_date = models.DateField(
verbose_name='Works with since:')
level = models.CharField("level", max_length=64, choices=LEVELS)
And I can't understand why my template code doesn't work
template.html
{{ user.employee.position }}
{{ user.employee.birth_date }}
{{ user.employee.summary }}
{% for i in user.employee.skills.all %}
{{ i.technology.name }}
{{ i.level }}
{% endfor %}
I can't see absolutely nothing. All models possible to see at adminpanel. And else then I using TemplateView such as
class AccountView(TemplateView):
template_name = "profile.html"
def get_context_data(self, **kwargs):
context = super(AccountView, self).get_context_data(**kwargs)
context['skills'] =
Skill.objects.filter(employee__user=self.request.user)
return context
then everything works fine.
There is something wrong with the modeling. You should use a OneToOneField between Employee and User. In essence an OneToOneField is a unique ForeignKey. It will however change some logic, such that user.employee will access the related Employee object, not a QuerySet of Employees:
class Employee(models.Model):
# ...
user = models.OneToOneField(
settings.AUTH_USER_MODEL,
on_delete=models.CASCADE,
related_name='employee'
)
# ...
In your AccountView, you unified 'skills' with the skills of that employee, indeed:
class AccountView(TemplateView):
template_name = "profile.html"
def get_context_data(self, **kwargs):
context = super(AccountView, self).get_context_data(**kwargs)
context.update(
skills=Skill.objects.filter(employee__user=self.request.user).select_related('technology')
)
return context
You might want to use .select_related(..) here to prevent the so-called "N+1 problem" where for each skill, you will make an extra query.
So you can render the skills with:
{% for skill in skills %}
{{ skill.technology.name }}
{{ skill.level }}
{% endfor %}
or you can access is through:
{% for skill in request.user.employee.employee_skills.all %}
{{ skill.technology.name }}
{{ skill.level }}
{% endfor %}
although the above is less safe, since it is possible that a User has no related Employee object.
Your Employee model currently has a one to many relationship with a user
class Employee(models.Model):
"""Employee information."""
user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name='employee', unique=True)
according to your comment you need a one to one relation ship so you need to change this to use a OneToOneField instead of a ForeignKey
Conceptually, this is similar to a ForeignKey with unique=True, but the “reverse” side of the relation will directly return a single object.
I'm new to Django and I'm trying to learn as I go. And I've ended up in a situation where I can't figure out what is the best way forward.
snippet from models.py:
class ProjectMeta(models.Model):
project = models.ForeignKey(Project)
architect = models.CharField(max_length=200)
landscape = models.CharField(max_length=100, blank=True)
engineer = models.CharField(max_length=200, blank=True)
client = models.CharField(max_length=100)
consultant = models.CharField(max_length=100, blank=True)
size = models.DecimalField(max_digits=5, decimal_places=2, blank=True)
location = models.CharField(max_length=200)
date = models.DateField()
STATUS = (
('CP', 'Competition'),
('UC', 'Under construction'),
('CO', 'Completed'),
)
status = models.CharField(max_length=2, choices=STATUS, default=1)
And this is the view:
class ProjectDetailView(DetailView):
model = Project
def get_context_data(self, **kwargs):
context = super(ProjectDetailView, self).get_context_data(**kwargs)
context['projectmeta_list'] = ProjectMeta.objects.all()
return context
But if I want to output ProjectMeta in the template I could iterate over projectmeta_list.
{% for metadata in projectmeta_list %}
<p>Architect: {{ metadata.architect }}</p>
{% endfor %}
But this require alot of repeating myself, and I wont work. Because lets say the architect field is empty, I would get Archiect: printed to the page. Is there a built-in way of converting a model into a dict or list, so I can iterate over it and only print out fields that aren't empty to the page?
I've been looking at get_fields(), would that work? https://docs.djangoproject.com/en/1.10/ref/models/meta/#retrieving-all-field-instances-of-a-model
I tried this in the shell, threw me and AttributeError:
>>> from projects.models import *
>>> Project._projectmeta.get_fields()
You should try wrapping the <p>Architect: {{ metadata.architect }}</p> piece in a conditional {% if metadata.architect != '' %} or some condition to that effect.
Try with another ProjectMeta model. Take a look at this one.
class ProjectMeta(models.Model):
project = models.ForeignKey(Project)
name = models.CharField(max_length=50)
value = models.TextField()
And this query should work. myproject.projectmeta_set.filter(name="status")
You can use built-in default or default_if_none template filters to show a default value if it is None or empty string.
{% for metadata in projectmeta_list %}
<p>Architect: {{ metadata.architect|default:"-" }}</p>
{% endfor %}
Check this for more details.
The problem is, when i'm trying to compare two properties which are the same when we check them in shell, but the condition is not complete and i have no idea why. I mean this condition: {% if c.author = member.name %}
views:
cvs = Cv.objects.all()
cv = Cv.objects.filter(author = request.user)
per = Person.objects.all()
gr = Group.objects.filter(members__name=request.user)
for c in cvs:
print c.author
mem = Membership.objects.all()
form = GroupForm()
context = {
'gr': gr,
'per':per,
'mem':mem,
'form': form,
'cvs':cvs,
'cv':cv,
}
return render(request, 'groups.html', context)
models.py:
class Cv(models.Model):
author = models.ForeignKey('auth.User')
name = models.CharField(max_length=25, null = True)
surname = models.CharField(max_length=25, null = True)
address = models.CharField(max_length=100, blank=True)
telephone = models.IntegerField()
birth_date = models.DateField(blank=True, null=True)
email = models.EmailField(max_length=50, null=True)
skills = models.TextField(null=True)
specialization = models.CharField(max_length=30, blank=True, null=True)
interests = models.TextField(blank=True, null=True)
summary = models.TextField(blank=True, null=True)
thumbnail = models.FileField(upload_to=get_upload_file_name, blank=True)
#property
def age(self):
return int((datetime.datetime.now().date() - self.birth_date).days / 365.25 )
def zapisz(self):
self.save()
def __str__(self):
return self.surname
class Person(models.Model):
name = models.CharField(max_length=128)
def __str__(self): # __unicode__ on Python 2
return self.name
class Group(models.Model):
name = models.CharField(max_length=128)
members = models.ManyToManyField(Person, through='Membership')
def __str__(self): # __unicode__ on Python 2
return self.name
class Membership(models.Model):
person = models.ForeignKey(Person)
leader = models.BooleanField(default=False)
group = models.ForeignKey(Group)
groups.html:
{% block profile %}
{% for g in gr %}
<div class="jumbotron">
<p><b>GROUP:</b> {{g.name}}</p>
{% for c in cvs %}
{% for member in g.members.all %}
{% if c.author = member.name %}
{{member.name}}
{% endif %}
{% endfor %}
{% endfor %}
</div>
{% endfor %}
{% endblock %}
Thanks for answer!
Firstly, please give your variables descriptive names. "c" and "gr" are impossible to understand.
Secondly, you are not comparing the right things at all. c.author is an instance of User; member is an instance of Person and member.name is a string. Comparing a User instance with a string will always fail.
Finally, this whole thing is horribly inefficient - and probably totally unnecessary. Three nested for loops means a huge number of iterations. If you could explain what the output needs to be, then we can almost certainly come up with a better way of doing it.
To test for equality in a Django template you need to use the equality operator == as follows:
{% if c.author == member.name %}
{{member.name}}
{% endif %}
You should compare c.name with member.name or c.author.first_name with member.name. So both of the variable to be strings.