>Replication works for managing read load, but it doesn't help manage write load. This is when you need automatic sharding. You've said 'need automatic shardin

>Replication works for managing read load, but it doesn't help manage write load. This is when you need automatic sharding. You've said 'need automatic sharding' multiple times now, but you've still yet to explain why you need it. Yes, sharding is important for write scaling. But it doesn't "need" to be automatic. Plenty of setups have completely capable manually sharded workloads running on MySQL. Some would consider the manual approach a plus, vs. relying on the database to automagically do it. It can be nice to have automatic sharding, assuming it works properly. But nice and needed are two different things, an I think it's an important distinction. You're basically saying if you shard you have to go with mongo and you can't go with anything that requires you manually handle it.