Ok, just persisted my first class today using hibernate by deploying Hibernate as a JBoss service using a MySQL DB. I must say it is so sweet and I think I will replace my CMPs with hibernate in the future. However, I ran into this newbe problem:

I have a class with an ID field using the uuid.string generator and my ID field in the DB get a "?" mark as the value?

Why would this be?

Tried searching the forum but I don't think the search engine does a good job on queriest including a ? mark.

mapping, small code, please.

I think the problem was the uuid.string ID generator. In my MySQL db, when the uuid.string generator was working, I was getting some really strange characters like arrows, smiley faces etc. However, most of the time the only value I got for my ID field was one question mark.

Once I changed the generator to uuid.hex, it worked right away. I don't know what experience others have had but I think MySQL, like PostgreSQL, might have some issues with the uuid.string generator.