Questions tagged [django-database-functions]
21 questions
22
votes
1 answer
How to make/use a custom database function in Django
Prologue:
This is a question arising often in SO:
Equivalent of PostGIS ST_MakeValid in Django GEOS
Geodjango: How to Buffer From Point
Get random point from django PolygonField
Django custom for complex Func (sql function)
and can be applied to…
John Moutafis
- 22,254
- 11
- 68
- 112
6
votes
4 answers
How to annotate a difference of datetime in days
I have a Booking model that has start and end datetime fields. I want to know how many days a booking covers. I can do this in Python but I need this value for further annotations.
Here's what I've tried:
In [1]:…
Oli
- 235,628
- 64
- 220
- 299
4
votes
0 answers
Django group by consecutive days (Friday, Saturday, Sunday)
I have an event that occurs everyday. Here is the model
class Event(models.Model):
date = models.DateField()
plays = models.IntegerField()
viewers = models.IntegerField()
time = models.FloatField()
I am trying to aggregate the…
atkawa7
- 461
- 1
- 6
- 13
3
votes
0 answers
How to filter an annotated queryset by - Window function - without changing the value of the annotated field
I have a queryset of users, after annotating the rank of each user using Django Window function, I want to query for a user without modifying the rank value
users_points_query = users.order_by(
'-total_points'
).annotate(
…
Mahdy H.
- 181
- 9
3
votes
1 answer
Filtering down through multiple ForeignKey relations in django
I am trying to get down through multiple-foreign key relationship where each Hotel has many Rooms, each Room has many Rateplans, each Rateplan has many Prices.
It resembles Christmas tree if you think about it:
Hotel
v
Room
v
Rateplan
v
Prices
How…
Kihaf
- 65
- 1
- 4
3
votes
1 answer
Django bulk update with data two tables over
I want to bulk update a table with data two tables over. A solution has been given for the simpler case mentioned in the documentation of:
Entry.objects.update(headline=F('blog__name'))
For that solution,…
AlanSE
- 2,597
- 2
- 29
- 22
1
vote
1 answer
django orm - annotate / aggregation (avg) in subquery
I have this model:
class UserMovieRel(models.Model):
user = models.ForeignKey("register.User", on_delete=models.CASCADE)
movie = models.ForeignKey("Movie", on_delete=models.CASCADE, related_name="users")
rating =…
Luke
- 1,794
- 10
- 43
- 70
1
vote
2 answers
SOLVED: Django ORM: How to round down (truncate) a query number?
SOLVED
I'm working with sensitive currency values. In my case, i have to reproduce a sheet with it's formulas.
The point is that i need to round down a currency value with 2 decimal places. A practical example is the number: 9809.4069, it should be…
Max Starke
- 23
- 3
1
vote
1 answer
How to get table data (including child table and sub child data) based on id which obtains from another table data? Django
views
company = Company.objects.get(id = company_id) # getting input from django urls ()
vehicles = CompanyContainVehicles.objects.filter(company_id=company.id) # Give all rows having same id (company.id)
all_vehicles =…
shraysalvi
- 303
- 1
- 10
1
vote
1 answer
Filter an object that has multiple related objects in Django
Let's say I have two models that have one-to-many relationships as the code below.
I'd like to only get order objects that have more than one shipment object.
The only way I can think of is getting it through a list comprehension [order for order in…
Lidia Kwon
- 31
- 1
1
vote
2 answers
Django annotate + SUM how to get all entries
My models
class Machine(models.Model):
machineName = models.CharField(verbose_name="Machine Name", max_length=20, blank=False, null=False)
class SalesReport(models.Model):
machine = models.ForeignKey(Machine, on_delete=models.CASCADE,…
Aravind OR
- 97
- 2
- 10
1
vote
2 answers
while connecting to MicrosoftSQL server using Django facing django.db.utils.OperationalError:
drivers available with me
**python shell**
'''In [2]: pyodbc.drivers()'''
**Output:**
**Out[2]: ['SQL Server']**
code in settings.py django:
**Settings.py in django**
'''# Database
#…
1
vote
1 answer
Compare year from DateTimeField/DateField Django ORM
I have a model configuration as below,
class Foo(models.Model):
start = models.DateTimeField()
end = models.DateTimeField()
How can I retrieve Foo instances with same Year?
Unsuccessfull try:
from django.db.models import…
JPG
- 82,442
- 19
- 127
- 206
1
vote
1 answer
How to link existing tables in database to Django Models?
I am learning Django and i need to know whether i can link a table already present in the database to a model (since, i heard that tables are created by Django for whatever models we are creating inside django app ).
If so, how can it be done?
sportymsk
- 43
- 1
- 8
0
votes
1 answer
Changing Year, Month, or Day in a Django model's date field using annotate
I have a Django model MyModel
class MyModel(models.Model):
"""My Model that stores date."""
date = models.DateField()
In my API I am receiving a param, review_month
I need to get all the entries in MyModel and replace their date's year…
Noyan Aziz
- 1
- 1