Hello there.

I need to add a new field to a database table that is already in production.
On top of that, my project is only going live a year from now. In the meantime, there will be other projects being released, and we are using XML files to define "switches" where we can turn some functionalities on and off.

The bottom line is: I cannot just add the column to the database and to the mapping class, since it will break the projects that will be released before mine.

What I was thinking is to have different mappings, one for the current table and another one to map the new table (that includes the new column).

Is this an easy thing to do with Hibernate? I mean, how will I create my classes and my mappings? Just extending my current class to have the new column wouldn't work, since I want to keep the storing mechanism the same (to avoid duplication.)

I've done some research but couldn't find solutions for this situations (probably because I'm not searching the right terms, since I don't have any experience with Hibernate.)

Any help will be greatly appreciated.

Thanks a lot!

1 year is too long and many things can change.

Best approach will be to work on a branch version of your code repository and merge your code with the main trunk and update the database when you ready to deploy to production. Obviously you will do all this in UAT/integration area before to check all the pieces are working correctly.

However, if you can this new column to database and update the map this column as @Transient which will tell hibernate to not persist/update this column.

When you ready to deploy your changes, take out the @Transient.


having said that, my personal opinion is not to add things to production when they are not needed. Working in a branch and keeping your branch updated with the latest trunk/head version will be my preferred option.

Oh sorry. I meant one month from now.

We're using trunk-based development for 2 years now and it's been amazing. We have a lot of people working on the same codebase and merging things around from several different branches is out of question.

Basically what I need is: depending on the value of one property, I will need to save and retrieve that column from the database. Is there another functionality that provides this @Transient behavior? I will obviously not be able to apply or not the annotation based on a property.

Thanks!