title: Oracle "create table as" null value
body: <p>If you create an Oracle table using "create as" where one of your fields is null you will get the error:</p>
  
  <blockquote>
    <p>ORA-01723: zero-length columns are not allowed</p>
  </blockquote>
  
  <p>Example query:</p>
  
  <pre><code>create table mytable as 
  select 
      field_a, 
      null brand_new_field
  from anothertable;
  </code></pre>
  
  <p>How can you get around this?  </p>