I am approaching to a GAE / GWT environment, coming from the RDBMS world.
Take, for instance, MySQL. If you want to do ANYTHING with your data, you can take a MySQL manager software, like PHP MyAdmin, Mysql Workbench and so on…
The datastore viewer on the appengine backoffice looks too simple to manage a complex model, I suppose, please correct me if I’m wrong.
Are there any tools ready to use?
The datastore viewer (in production, at http://appengine.google.com/, on the dev server at http://localhost:8080/_ah/admin/) is the only commonly used tool for this. Is there something in particular you want to do that it can’t accomplish?
Bear in mind that the App Engine datastore is a nonrelational database. ‘Tables’ don’t exist, there’s no fixed schema, and queries like joins and group by aren’t supported. This means a lot of the features you might be used to in tools like PHPMyAdmin don’t apply here.