title: How to handle changes in duplicated data in NoSQL
body: <p>We're evaluating NoSQL for an upcoming project. I tend to think of things in a RDBMS way and am having trouble conceptualizing the lack of normalization. </p>
  
  <p>I understand that duplicating data is not considered wrong in NoSQL. What I'm having trouble understanding is fixing changes to data to prevent anomalies.</p>
  
  <p><strong>Explanation of Question by Example:</strong></p>
  
  <blockquote>
    <p>You are organizing a series of poker tournaments. You have players,
    locations, and tournament events. As I understand it, a tournament
    event might contain a location and a collection of players. It does
    not need to have all the player data, but if you want to get the names
    and home addresses of everyone going to the next tournament, that info
    should be in the tournament collection.</p>
    
    <p>Someone has gotten married and moved, changing their last name and
    address. Does the application need to update the player collection and
    the tournament collection? Or is my model of the collections wrong? How do
    developers "keep track" of where information is duplicated? </p>
  </blockquote>