Smooth React virtual scroll with fixed rows/columns
One of our ongoing projects, Neptyne, introduces an Excel-like grid written in React. We used a library to apply virtual scroll to it, but we stumbled upon a problem with fixed rows and columns inside the grid. Here I would like to describe this problem, how it occurs, and how we handled it.
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.
Increasing performance by using proper query structure
Earlier in our previous article "Improve efficiency of your SELECT queries" we discussed ways to profile and optimize the performance of SELECT queries. However, to write complex yet efficient SQL queries, there is a thing to remember about.
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>