I'm reading the hibernate reference, but i had a question, which i i searched for it on the internet but i couldn't find a good answer.
Can anyone of the experts here explain to me , or refer to me a document which explain the "hbm2ddl.auto" property?

im no an expert but the propertie sets how the database-schema is beeing influenced by hibernate when the sessionfactory is created and/or closed:


- if you have a working database you dont want to set this property
- if you want hibernate you export changes made in your mappin-files automatically to your existing schema (so you dont have to type the sql's on your own) you should set this property to "update". this is usefull for testing
- if you dont want to create the schema typing your sqls (lets say you have an empty database) you can set the property to "create" and hibernate will do it for you
- validate - well it validates your mapping against your existing schema
- create-drop creates the schema and drops it after the sessionfactory is closed


take a look at:
http://www.hibernate.org/hib_docs/refer ... ation.html
especially 3.7

just play around with the setting ...

Thanks so much for your help :-)