title: Replace nulls values in sql using select statement in mysql?
body: <p>Ho to do this?
  What query can be written by using <strong>select</strong> statement where all nulls should be replaced with 123?</p>
  
  <p>I know we can do this y using, 
      update tablename set fieldname = "123" where fieldname is null;</p>
  
  <p>but can't do it using <strong>select</strong> statement.</p>