title: Slow query execution in an empty table. (after deleting a large amount of inserts)
body: <p>I have a table in an oracle database with 15 fields.
  This table had 3500000 inserts. I deleted them all.</p>
  
  <pre><code>delete
  from table
  </code></pre>
  
  <p>After that, whenever I execute a select statement<br>
  I get a very slow response (7 sec) even though the table is empty.
  I get a normal response only in the case that I search
  according to an indexed field.</p>
  
  <p>Why?</p>