title: How to replace NULL with white space in Azure Data Factory for all data types?
body: <p>I have columns of different data types. For example, some column has int type, other is date and another is string type.</p>
  <p>When I use <code>iifNull(column1, ' ')</code>
  it works only for string data type.</p>
  <p>Moreover, when I have date column and I use as below code, the result is still NULL</p>
  <pre><code>iifNull(datecol, toTimestamp('1990-01-01', 'yyy-MM-dd'))
  </code></pre>
  <ol>
  <li>How to replace integer and date columns NULL values with white space then?</li>
  <li>How to work with date column?</li>
  </ol>