title: AWS Quicksight if else with dates
body: <p>I am trying to merge two date columns together with the ifelse function, my formula is</p>
  <p><code>ifelse(RewardPaidDate = null,rewarddate, RewardPaidDate)</code></p>
  <p>however it only returns the RewardPaidDate column and leaves the nulls in the new calculated field named RewardSentDate. I have tried changing it to</p>
  <p><code>ifelse(RewardPaidDate = '',rewarddate, RewardPaidDate)</code></p>
  <p>but I get the error message:
  &quot;At least one of the arguments in this function does not have correct type. Correct the expression and choose Create again.&quot;</p>
  <p><a href="https://i.stack.imgur.com/MxHq8.png" rel="nofollow noreferrer">calculated column is RewardSentDate</a></p>