[jpgvm]

Generally you don't have your main application database also serve as your data warehouse for lots of reasons.

Generally you offload that to purpose built systems that favor those aforementioned tradeoffs or onto services that run them for you, i.e BigQuery, Snowflake, etc.

Your main application database is unlikely to need sharding unless you really do have a phenomenal amount of customers or you need regional sharding to meet legal requirements about data sovereignty for example.