title: Why should I have multiple collections in a NoSql database (MongoDB)
body: <p>Example:
  If I have a database, let's call it <code>world</code>, then I can have a collection of countries.</p>
  
  <p>The collection can have documents, one example on a document:</p>
  
  <pre><code>"_id" : "hiqgfuywefowehfnqfdqfe",
  "name" : "Italy",
  cities : {{"_id": "ihevfbwyfv", name : "Napoli"}, {"_id: "hjbyiu", name: "Milano"}}
  </code></pre>
  
  <p>Why should I or when should I create a new collection of documents, I could expand my documents inside my world collection instead of creating a new collection.</p>
  
  <p>Is creating a new collection not like creating a new domain?</p>