April 2019
Beginner to intermediate
244 pages
6h 34m
English
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Chapter 4Making Changes with Changesets
At the end of the last chapter, we saw how schemas provide a quick method for inserting new records into the database, even with associated records. But a database is only as good as the quality of the data that it contains, so we need to be careful about the modifications we make to that data. The Ecto.Changeset module provides a rich data structure and a wide array of functions that helps us manage making changes safely and securely.
In this chapter, we will take a deep dive into the world of changesets. We will start by taking a high-level look at the process of making a change, then look at each step of the process in detail: casting and filtering user-provided data, validating the data, and capturing ...
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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.
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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.