Does reverse engeneering delete Tables?

barnti · **Joined:** Mon May 22, 2006 8:32 am **Posts:** 67

Hi,

after using reverse engeneering from JDBC connection twice all tables are empty. Does reverse engeneering delete data from used tables?

Urgent! What has happened?

Regards,

a.k.

pauldale · **Joined:** Fri Jun 16, 2006 10:48 am **Posts:** 3

I also had a table wiped after using "reverse engineering"

Definitely not the behaviour I was expecting ...

If this was intended behaviour at a bare minimum it should give a warning before doing something like dropping a table that has data in it.

barnti · **Joined:** Mon May 22, 2006 8:32 am **Posts:** 67

pauldale wrote:

I also had a table wiped after using "reverse engineering"

Definitely not the behaviour I was expecting ...

If this was intended behaviour at a bare minimum it should give a warning before doing something like dropping a table that has data in it.

So it is true!? All data gone by using reverse engeneering. Any more infos about that? If that is what reverse engeneering does Hibernate tools are quite useless...?!

Regards,

a.k.

pauldale · **Joined:** Fri Jun 16, 2006 10:48 am **Posts:** 3

Yes, I am sure the hibernate tools wiped a table without telling me that it was going to do so or that it had been done.

barnti · **Joined:** Mon May 22, 2006 8:32 am **Posts:** 67

Hi,

pauldale wrote:

Yes, I am sure the hibernate tools wiped a table without telling me that it was going to do so or that it had been done.

So the best way to use Htools may be not to use or switch the dbuser before using reverse engeneering...

Thanks for your answers. I am looking forward for more in this discussion.

@max: Can you say anything about that?

Regards,

a.k.

max · **Posted:** Sat Jun 17, 2006 3:47 am

i guarantee you that we don't delete any tables during reverse engineering.

What you might have done is to enable hbm2ddl.auto to some setting that drop-create tables ? Could that be the case ?

barnti · **Joined:** Mon May 22, 2006 8:32 am **Posts:** 67

Hi Max,

max wrote:

i guarantee you that we don't delete any tables during reverse engineering.

What you might have done is to enable hbm2ddl.auto to some setting that drop-create tables ? Could that be the case ?

I don't know where to set this. Can you tell me where to find this "hbm2ddl.auto"? What to do to get rid of this?

Thanks for advice,

regards,

a.k.

max · **Posted:** Sat Jun 17, 2006 11:23 am

it is normally set in either hibernate.properties or hibernate.cfg.xml

pauldale · **Joined:** Fri Jun 16, 2006 10:48 am **Posts:** 3

Well, what I can say is that absolutely nothing was touching that tables except for the Hibernate Tools.

I can also say that after using the Hibernate Tools that table no longer had any of its data and had been recreated with only the two columns that were mapped in the .hbm.xml

I can also say that at no point was there any indication in any of the dialogs or labels of fields within the tool that this would be what would happen.

As I posted before, in my opinion dropping an existing table, especially one containing data, without a warning is bad behaviour.

It seems to me that it would be a good idea to add a warning before executing this potentially dangerous operation and better yet to even check if there is data in the table and give a more serious warning.

barnti · **Joined:** Mon May 22, 2006 8:32 am **Posts:** 67

Hi,

max wrote:

it is normally set in either hibernate.properties or hibernate.cfg.xml

Yes, i eliminated this. Seems to happen i copied this property from a locale hibernate.cfg.xml to production stage. My fault.

When is this configuration to be executed? During reverse engeneering process? Or just when i open and close the SessionFactory?

Thanks so far!

Regards,

a.k.

max · **Posted:** Mon Jun 19, 2006 8:21 am

it is executed when you build a sessionfactory (as explained in docs).

Using the tools = using hibernate

I'll see if i can put in a "safety" button.