title: How to add a file to a dvc-tracked folder without pulling the whole folder's content?
body: <p>Let's say I am working inside a git/dvc repo. There is a folder <code>data</code> containing 100k small files. I track it with DVC as a single element, as recommended by the doc:</p>
  <pre class="lang-sh prettyprint-override"><code>dvc add data
  </code></pre>
  <p>and because in my experience, DVC is kinda slow when tracking that many files one by one.</p>
  <p>I clone the repo on another workspace, and now I have the <code>data.dvc</code> file locally but none of the actual files inside yet. I want to add a file named <code>newfile.txt</code> to the <code>data</code> folder and track it with DVC. Is there a way to do this <em>without pulling the whole content of <code>data</code> locally</em> ?</p>
  <p>What I have tried for now:</p>
  <ol>
  <li><p>Adding the <code>data</code> folder again:</p>
  <pre><code>mkdir data
  mv path/to/newfile.txt data/newfile.txt
  dvc add data
  </code></pre>
  <p>The <code>data.dvc</code> file is built again from the local state of <code>data</code> which only contains <code>newfile.txt</code> so this doesn't work.</p>
  </li>
  <li><p>Adding the file as a single element in <code>data</code> folder:</p>
  <pre><code> dvc add data/newfile.txt
  </code></pre>
  <p>I get :</p>
  <pre><code> Cannot add 'data/newfile.txt', because it is overlapping with other DVC tracked output: 'data'. 
   To include 'data/newfile.txt' in 'data', run 'dvc commit data.dvc'
  </code></pre>
  </li>
  <li><p>Using dvc commit as suggested</p>
  <pre><code> mkdir data
   mv path/to/newfile.txt data/newfile.txt
   dvc commit data.dvc
  </code></pre>
  <p>Similarly as 1., the <code>data.dvc</code> is rebuilt again from local state of <code>data</code>.</p>
  </li>
  </ol>