Back
Sep 23, 2010

OR and AND without django.db.models.Q

I just found out that orand andare defined for QuerySet. This means that to do queries union or intersection, you can do:

User.objects.filter(...) | User.objects.filter(...)
User.objects.filter(...) & User.objects.filter(...)

Subscribe for the news and updates

More thoughts
Feb 3, 2025Technology
Figma for Developers: What Dev Mode Offers and How to Use It

This article explores Figma’s Dev Mode, a tool that streamlines design-to-code translation by enabling precise inspection, automated code generation, and seamless integration with design systems.

Mar 18, 2024Technology
From boring to exciting: turn learning to code into an adventure

Tired of boring programming courses where you're forced to read thick textbooks and write code that's never used? Need a platform that makes learning fun and exciting? Then you're in the right place!

May 10, 2018Technology
How to Build a Cloud-Based Leads Management System for Universities

Lead management is an important part of the marketing strategy of every company of any size. Besides automating various business processes, privately-held organizations should consider implementing an IT solution that would help them manage their leads. So, how should you make a web-based leads management system for a University in order to significantly increase sales?

Mar 4, 2011Technology
Css sprite generation

I've created this small sprite to create css sprites. It glues images from directory directory into single file and generates corresponding css.

Sep 23, 2010Technology
Dynamic class generation, QuerySetManager and use_for_related_fields

It appears that not everyone knows that in python you can create classes dynamically without metaclasses. I'll show an example of how to do it.So we've learned how to use custom QuerySet to chain requests:Article.objects.old().public()Now we need to make it work for related objects:user.articles.old().public()This is done using use_for_related_fields, but it needs a little trick.

Feb 18, 2010Technology
Absolute urls in models

Everybody knows about permalink, but it's usually used only in get_absolute_url. I prefer to use it for all related model urls.class Event(models.Model):# ...@models.permalinkdef edit_url(self):return ('event_edit', (self.pk, ))And then in template:<a href="{{ event.edit_url }}">Редактировать событие</a>