March 2025
Intermediate to advanced
202 pages
4h 45m
English
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Projecting a Leaderboard
Leaderboards are an ideal example of projections. They take a long stream of data and distill it down to a very small bit of summarized information. Most leaderboards of any size can take prohibitively long to generate, which reinforces the need for a separation of read and write models.
Let’s consider a video game in which the goal is to kill zombies. You want to generate a leaderboard that shows the top 10 most prolific zombie slayers of all time. To produce this on demand, you would have to query the entire history of zombie kills from the game’s release day until the present day.
The following is an example of the leaderboard you’ll generate for this game that shows the top 10 zombie killers of all time.
Table 1. ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.