title: Create n columns on bigquery
body: <p>I want to generate a new table in bigquery using months between two dates (let's say from 2016-01-01 until 2019-05-01)</p>
  
  <p>I know how to generate an array of months, such as</p>
  
  <pre><code>  SELECT
      GENERATE_DATE_ARRAY('2016-01-01', '2019-05-01', INTERVAL 1 MONTH) AS months
  </code></pre>
  
  <p>How do I create columns for each of the month generated in the array above?
  I want to create a counter month by month, having months as columns</p>