HC-tree is an experimental high-concurrency database back end for SQLite
Can someone explain why you would want a database larger than 16 TiB? Imagine there's database corruption, or you need to change the schema or something... why would you want to deal with that on an insane scale like hundreds of TiB? If you split your data up into smaller databases or shard, there's less chance of a problem affecting all of your data, and it being so gigantic that it takes forever to fix it.