title: Hibernate : hbm2ddl.auto value="update" or "none"
body: <p>I'm using JPA via Hibernate... </p>
  
  <p>In my persistence.xml I configure hibernate to update the schema as follow : </p>
  
  <pre><code> &lt;property name="hibernate.hbm2ddl.auto" value="update"/&gt;
  </code></pre>
  
  <p>Is it better to let JPA manage our databases or is it better to manage the databases ourselves (manually) ...</p>
  
  <pre><code>   &lt;property name="hibernate.hbm2ddl.auto" value="none"/&gt;
  </code></pre>
  
  <p>The senior developers I know said to me that the second method is better ... because it is a habit the DBA do in all good entreprises .. but I want to have more explanation ... I want to know why the second method is better? why we should not let JPA manage the tables and the relations it self ... </p>