title: Spaces when concatenating multiple columns and one column is null - Oracle
body: <p>I need to concatenate several columns into one, with spaces between each value. The problem is when one value is null, I end up with a double space between two values. </p>
  
  <p>Example</p>
  
  <pre><code>SELECT (FIRST_NAME || ' ' || MIDDLE_NAME || ' ' || LAST_NAME
    FROM TABLE_A;
  </code></pre>
  
  <p>If the middle name happens to be NULL, then I end up with two spaces between the first and last name. Any way to get around this and only have one space when there's a null value?</p>