title: Mentioning column names in select for derived tables
body: <p>i have doubt,</p>
  
  <pre><code>select *   
  from  
  (  
       select *  
       (  
           select User_Id,User_Name,Password  
           from &lt;table&gt; T  
           where  IsActive = 1  
       ) k   
  ) m
  </code></pre>
  
  <p>in this case, is it required to mention column names in other 2 select statements,</p>
  
  <p>mentioning columns is always better than keeping *</p>
  
  <p>but,what is the use actually in above top 2 selects as we are getting selected columns from derived tables..</p>