In the new Juno release of Eclipse SDK, the Database Structure view does not seem to show anything. This may be a side effect of the fact that connecting to a database also no longer immediately opens a new SQL Editor window.
Closing the database structure window and then opening it again from the right click menu on the database connection will display a working database structure.
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Closing the database structure window and then opening it again from the right click menu on the database connection will display a working database structure.