title: Oracle SQL ability to add filter on Sysdate which accepts negative and posstive values in days
body: <p>SQL newb here. I'm trying to adjust the filters in my Oracle SQL report, I would like the filter to accept both negative (-) and possitive (+) values.</p>
  <p>This is my SQL line:</p>
  <pre><code>Work_day &lt;= to_date(sysdate+'&amp;Days_from_current_date')
  </code></pre>
  <p>Problem I'm only able to add + days from the sysdate, I would like to have filter which would accepts:</p>
  <pre><code>-XX days from the sysdate
  +XX days from the sysdate
  </code></pre>