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
In one of our recent projects, we had an interesting case: the whole application was built around an interactive map for a fairly large shopping mall, and the main goal of the system was to plot the closest route to a user-selected destination.
Django ORM is a very abstract and flexible API. But if you do not know exactly how it works, you will likely end up with slow and heavy views, if you have not already. So, this article provides practical solutions to N+1 and high loading time issues. For clarity, I will create a simple view that demonstrates common ORM query problems and shows frequently used practices.
Now it's time to get acquainted with Elasticsearch. This NoSQL database is used to store logs, analyze information and - most importantly - search.
For any project there may be a need to use a database full-text search. We expect high speed and relevant results from this search. When we face such problem, we usually think about Solr, ElasticSearch, Sphinx, AWS CloudSearch, etc. But in this article we will talk about PostgreSQL. Starting from version 8.3, a full-text search support in PostgreSQL is available. Let's look at how it is implemented in the DBMS itself.
In my current project I had a task to use twitter API. Twitter uses OAuth for authentication, which is pretty dreary. To avoid fiddling with it all the time, I've moved authentication to decorator. If key is available - nothing happens, just view is launched as usual. It's convenient that there's no need for additional twitter settings in user profile. Code is in article.
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>