title: How to select data between two dates using only the start date?
body: <p>I have problem select data between two dates if the only start_date is available.</p>
  <p>The example I want to see is what discount_nr was active between 2020-07-01 and 2020-07-15 or only one day 2020-07-14. I tried different solutions, date range, generate series, and so on, but was still not able to get it to work.</p>
  <p>Table only have start dates, no end dates</p>
  <p>Example:</p>
  <pre><code>discount_nr, start_date
  1, 2020-06-30
  2, 2020-07-03
  3, 2020-07-10
  4, 2020-07-15
  </code></pre>