It’s over here! It was originally a fan project, and then they bought it and declared it to be the official database.
I really do feel that it falls short of what is needed in an official database. But I want to be clear that I don’t mean that as a criticism of its creator. I’m very much inclined to assume the major problems are more to do with FFG’s management of it than anything else.
I will happily admit that its deckbuilding interface provides something very different from the other available deckbuilders. I personally am not a fan, but I know there are people who are, so I’m glad it exists for them.