Hibernate hbm2ddl.auto default value

What is the default value of hibernate.hbm2ddl.auto in the hibernate cfg file mapping? Is it possible to remove

<property name="hibernate.hbm2ddl.auto">update</property>

from the config file? If I remove this property will it affect my DB???

Automatically validates or exports schema DDL to the database when the SessionFactory is created. With create-drop, the database schema will be dropped when the SessionFactory is closed explicitly.

validate | update | create | create-drop

• validate- existing schema
• update- only update your schema once created
• create- create schema every time