The upgrade procedure is described in this page. You'll be able to upgrade OSDE very easily, because Eclipse does everything.
You can upgrade this OSDE with Software Updates.
Launch your Eclipse IDE which has the previous version of OSDE.
Due to open the dialog for upgrading plug-in, you select the following menus.
You can upgrade OSDE according to the following:
If you have an old OSDE, you can find the new version of OSDE in Available Updates dialog.
Eclipse starts to download and install new OSDE. If the intalling task has succeed, you can see the dialog to specify restarting Eclipse.
Upgrade complete after restarting Eclipse.