Tag: django-queryset

Querying One model item from another model

django django-models django-queryset django-views python

I have a list of Artist (Musicians) and their Albums they created. T My models looks like the following: My Views My HTML is the following: My shell looks like the following: I would like to learn how to select One artist “Eminem” and have all albums associated with his model listed on the next pa…

Django query for column value search?

django django-models django-queryset postgresql python

What is the Django query for this? DB data – I only need record that contain “1.2.3” values not like – (“Cat 1.2.3” or “1.2.3-XY2” or any such value). And pattern “1.2.3” can be anywhere in column where column value can have comma separated values to…

Rendering highest integer value from three models instances in django

django django-annotate django-models django-queryset python

I have three models which are related all to one model. I am rendering MyParentModel in DetailView (CBV) and passing related models as a context to render individual models ‘ranking’ field on the same template. Now I need to render same ‘ranking’ on MyParentModel ListView, but I only w…

How to join linked models with foreign key?

django django-models django-orm django-queryset python

I’m coming from Java and new to python / django. So may be my question is silly … I have one class Parent which contains an association with a class Child. Parent refers to its ‘Childs’ through the related name ‘children’. At Run time it works well, but at design time, it i…

How to sum with condition in a Django queryset

django django-queryset python

I am trying to sum Django query with a condition. Suppose I have got some data like this: And these types are string and they have values, like x = 1, y = 25, z = -3 How can I sum up all the values without a loop? Currently using a loop. Answer To perform the calculation inside the database

Access Django M2M values in queryset without looping

django django-models django-queryset python

I receive some data through Ajax that allows me to do some filtering on a model that has some m2m relations (say Model). I get a queryset, say “content” that I then need to send back using json. Here are simplified lines of code: It was working fine but the project changed and I now need to includ…

django FieldError: Cannot resolve keyword ‘category_name_contains’ into field. Choices are: category, description, id, image, name, order, price

django django-models django-queryset django-views python

I want to build a food delivering app, but facing this error. “FieldError: Cannot resolve keyword ‘category_name_contains’ into field. Choices are: catego ry, description, id, image, name, order, price”. This is the query.py: This is the views.py This is my models.py: Here’s the …

How to apply a for statement to simplify repeated code in Django queryset

django django-queryset python

The filter is applied according to team_parameter(request.GET.get(‘team)) and it has very repetitive code. At the end of the if statement, no filter is applied only if team_parameter is ‘ALL’. I think a for statement is necessary to minimize this code, but I did not know how to apply it, so …

Flitering django queryset based on ManyToManyField

django django-queryset many-to-many python

In my Request model, there is a field requested_to which is a ManyToManyField I want to filter queryset of Request model where a organization_user is not in requested_to Answer You can filter with: Django makes LEFT OUTER JOINs when you filter on a ManyToManyField (or a reverse ForeignKey), so here we exclude…

Django merge QuerySet while keeping the order

django django-models django-queryset python

i’m trying to join together 2 QuerySets. Right now, I’m using the | operator, but doing it this way won’t function as an “append”. My current code is: I need the elements from querysetA to be before querysetB. Is it even possible to accomplish while keeping them just queries? Ans…