tutorial
http://www.hibernate.org/hib_docs/v3/reference/en/html/tutorial.html
here is config file from this tutorial
===========

<hibernate-mapping>

   <class name="Event" table="EVENTS">
       <id name="id" column="EVENT_ID"> // why type is missing here ?
           <generator class="increment"/>
       </id>
       <property name="date" type="timestamp" column="EVENT_DATE"/> //
type is here.
       <property name="title"/> // why type is missing here ?
   </class>

</hibernate-mapping>

i am surprised to see that some cases in the above "type" has been
mentioned and some other cases "type" has been skipped .

why it is like this ?