title: Oracle: Insert into select... in the
body: <p>What is the advantage of inserting into a select of a table over simply inserting into the table?</p>
  
  <p>eg</p>
  
  <pre><code>insert into
  ( select COL1
         , COL2
    from   Table1
    where  1=2                  &lt;= this and above is the focus of the question.
  ) select COL3, COL4 from Table2 ;
  </code></pre>
  
  <p>It seems to do the same thing as:</p>
  
  <pre><code>insert into Table1
  ( COL1, COL2 )
  select COL3, COL4 from Table2 ;
  </code></pre>
  
  <p>This is the first time I've seen this; our Sr Dev says there is some advantage but he can't remember what it is.</p>
  
  <p>It may make sense in a way if one was inserting a "select *..." from a table with lots of columns, and we want to be lazy, but... we're not. We're enumerating each column in the table.</p>
  
  <p>Database is Oracle 11gR2, but this query was written probably in 10g or before.</p>