title: How to remove multiple commas but keep one in between two values in a csv file?
body: <p>I have a csv file with millions of records like below </p>
  
  <pre><code>1,,,,,,,,,,a,,,,,,,,,,,,,,,,4,,,,,,,,,,,,,,,456,,,,,,,,,,,,,,,,,,,,,3455,,,,,,,,,,
  1,,,,,,,,,,b,,,,,,,,,,,,,,,,5,,,,,,,,,,,,,,,467,,,,,,,,,,,,,,,,,,,,,3445,,,,,,,,,,
  2,,,,,,,,,,c,,,,,,,,,,,,,,,,6,,,,,,,,,,,,,,,567,,,,,,,,,,,,,,,,,,,,,4656,,,,,,,,,,
  </code></pre>
  
  <p>I have to remove the extra commas between two values and keep only one. The output for the sample input should look like</p>
  
  <pre><code>1,a,4,456,3455
  1,b,5,467,3445
  2,c,6,567,4656
  </code></pre>
  
  <p>How can I achieve this using shell since it automates for the other files too.
  I need to load this data in to a database. Can we do it using R?</p>