title: How to merge base and multiple delta structured streams in Azure DataLake
body: <p>I have a base stream and I have multiple delta streams for different consecutive dates. I want to merge them to get the final stream. How can I accomplish this in Azure Datalake. For example assume these are the stream. I need to merge these streams to get the final stream. Merge would replace the original value with the new value. The number of delta stream as of now is more than 100.</p>
  
  <p><strong>Base Stream:</strong></p>
  
  <pre><code>1022918 300.00  300.00  2   7   5   100
  1022918 400.00  400.00  2   170 5   100
  1022919 1000.00 1000.00 2   7   6   100
  1022920 2000.00 2000.00 2   170 6   100
  1022921 3000.00 3000.00 2   123 7   100
  1022922 100.00  100.00  2   162 7   100
  1022922 200.00  200.00  2   123 9   100
  1022922 300.00  300.00  2   162 9   100
  </code></pre>
  
  <p><strong>Delta Stream 1:</strong></p>
  
  <pre><code>1022918 400.00  300.00  2   7   5   100
  1022919 2000.00 1000.00 2   7   6   100
  1022920 3000.00 2000.00 2   170 6   100
  1022922 400.00  300.00  2   162 9   100
  </code></pre>
  
  <p><strong>Delta Stream 2:</strong></p>
  
  <pre><code>1022919 2500.00 1000.00 2   7   6   100
  1022920 3500.00 2000.00 2   170 6   100
  </code></pre>
  
  <p><strong>Expected Output</strong></p>
  
  <pre><code>1022918 400.00  300.00  2   7   5   100
  1022918 400.00  400.00  2   170 5   100
  1022919 2500.00 1000.00 2   7   6   100
  1022920 3500.00 2000.00 2   170 6   100
  1022921 3000.00 3000.00 2   123 7   100
  1022922 100.00  100.00  2   162 7   100
  1022922 200.00  200.00  2   123 9   100
  1022922 400.00  300.00  2   162 9   100
  </code></pre>