Comment 3 for bug 1396427

there be dragons here.

it's quite possible the deployer had trove deployed pre-datastores, which means if you flipped active=0, datastore-list would return nothing. when we did this upgrade, we simply changed the name from "Legacy MySQL" to "mysql" and that was that (the instance provisioning still worked).

as to why the name "Legacy MySQL" was chosen: not sure.