Working with the Java Play! framework for some months now, I've just (sic!) discovered the Web database interface on H2 throught the url http://localhost:9000/@db
A first page will ask you to configure the database connection:
fig. 1 – Connection management page on embedded H2 database
And the you are able to query as you want any table from the H2 database:
fig. 2 – Browse interface on "mydatabase" instance
Have fun (again) with Play!framework .