<h1 id="projection">Projection<a aria-hidden="true" class="anchor-heading icon-link" href="#projection"></a></h1>
<h2 id="claim"><a href="/wiki/notes/6g9uoqnz66x1nwq5wb418hi">Claim</a><a aria-hidden="true" class="anchor-heading icon-link" href="#claim"></a></h2>
<h3 id="projection-implementations-tend-to-have-a-couple-of-moving-parts">projection implementations tend to have a couple of moving parts<a aria-hidden="true" class="anchor-heading icon-link" href="#projection-implementations-tend-to-have-a-couple-of-moving-parts"></a></h3>
<ul>
<li>A repository that allows to find or store a state</li>
<li>A projector that has event handlers that know how to update or create a state</li>
</ul>
<h3 id="the-only-difference-between-projection-and-aggregate-is-intent">the only difference between <a href="/wiki/notes/py9r8c41at3tcwrquyroj10">Projection</a> and <a href="/wiki/notes/7bk6xdj2n91yktvfjvs92j1">Aggregate</a> is intent<a aria-hidden="true" class="anchor-heading icon-link" href="#the-only-difference-between-projection-and-aggregate-is-intent"></a></h3>
<ul>
<li>Internal aggregate state exists so that we can make a decision if a command should be processed, and if yes then what are the new events that should be persisted (so the C from CQRS). </li>
<li>On the other hand projections always answer a question about the facts that already happened to the system (the Q part of CQRS).</li>
</ul>
<h2 id="resources">Resources<a aria-hidden="true" class="anchor-heading icon-link" href="#resources"></a></h2>
<ul>
<li><a href="/wiki/notes/xm07l41ykpnpj6xuooxkslt">Event Sourcing Projections</a></li>
</ul>
<hr>
<strong>Backlinks</strong>
<ul>
<li><a href="/wiki/notes/xm07l41ykpnpj6xuooxkslt">Event Sourcing Projections</a></li>
<li><a href="/wiki/notes/py9r8c41at3tcwrquyroj10">Projection</a></li>
</ul>

projection implementations tend to have a couple of moving parts

the only difference between  and  is intent

Projection

public-notes


Welcome! And beware!  

## Purpose

This vault is the "[[learning-in-public|ar.swyx.learn-in-public]]" part of my Second Brain. If you share some of my interests, please [reach out](https://djradon.github.io)! 

## Contents

- [[t]] my personal wikipedia
- [[idea]] (not necessarily mine)
- Resource Notes, including highlights, thoughts and metadata, for various things:
  - [[ar]] mostly articles, papers and web pages
  - [[book]]
  - [[community]]
  - [[course]]
  - [[event]]
  - [[game]]
  - [[loc]]
  - [[org]]
  - [[user]] 
  - [[prdct]] mostly software products, but also ontologies
  - [[recipe]]
  - [[video]] movies, tv episodes, youtube, etc
- [[vs]]
- [[wanted]]
- Some "Metadata Notes":
  - [[tags]] which may refer to any and multiple (or none) of the above
  - [[c]]: ways to categorize resources
  - [[p]]: ways to assert things about resources (mostly abandoned)

In terms of the [[t.km.zettelkasten]] method, this wiki is a commingling of literature notes with something @Sönke-Ahrens warned about: a "personal Wikipedia or a database" [^1]. 

In terms of [[t.tm.getting-things-done]], it's references, someday-maybe, next actions, and public projects.

## Beware!

This is a cluttered cupboard of jumbled jottings riddled with inaccuracies, confusion, and mistakes.

## What This Is Not

- evergreen-notes/digital-garden: for "synthesized" / original-ish publishable big-idea notes that should evolve over time, props to @andy-matuschak and @maggie-appleton
- blog: for "point-in-time" items to be shared: personal news, articles, etc.
  - e.g., [[ar.substack.carpe-noctem]]


[^1]: [[book.how-to-take-smart-notes]]  

Projection

Claim

projection implementations tend to have a couple of moving parts

the only difference between Projection and Aggregate is intent

Resources