title: Find columns with non zero values in Hive
body: <p>Let's say you have a database with <code>n</code> columns, from <code>col1</code> to <code>coln</code>, where <code>n</code> is large. </p>
  
  <p>Would it be possible to find all rows such that at least one column from <code>colk</code> to <code>coln</code> has a non zero value (assuming columns are  non-negative numbers, and numbers may be missing)?</p>