title: SQL not equals & null
body: <p>We'd like to write this query:</p>
  
  <pre><code>select * from table 
  where col1 != 'blah' and col2 = 'something'
  </code></pre>
  
  <p>We want the query to include rows where col1 is null (and col2 = 'something').  Currently the query won't do this for the rows where col1 is null.  Is the below query the best and fastest way?</p>
  
  <pre><code>select * from table 
  where (col1 != 'blah' or col1 is null) and col2 = 'something'
  </code></pre>
  
  <p>Alternatively, we could if needed update all the col1 null values to empty strings.  Would this be a better approach?  Then our first query would work.</p>
  
  <hr>
  
  <p><strong>Update</strong>: Re: using NVL: I've read on another <a href="https://stackoverflow.com/questions/191640/get-null-null-in-sql">post</a> that this is not considered a great option from a performance perspective.</p>