In a scenario where you have a rather complex domain model (20+ interliked tables) and a lot of time series data (multiple TB, references to the domain model), would you use two different DBMS, one to store the data from the domain model (e.g. PostgreSQL) and the other to store the time series data (e.g. QuestDB)?
Or is it considered best practice to move the domain model to the time series database or the time series data to the domain model database (e.g. TimescaleDB)?
Pros of separate DBMS:
- separation of concerns
- performance (optimized time series access)
- compression (optimited time series compression)
Cons of separate DBMS:
- no referential integrity
- no "direct" JOINS with the domain model possible