I have managed/architected/developed med-to-large transactional SQL Server implementations for 17+ years. In-Memory vs temp, CTEs, query optimization/design, partitioned tables/indexes, file groups, scalability, maintainability... I have come across a lot in 17+ years and worked around/fixed/debugged a lot of different implementations. While SQL Server is natively not the most scalable data store available, its price-performance+reliability is still tough to beat. Single DB instance experience; Max Tx DB: 350GB Max Tx/Month: 10TB Max Table Size: > 1B rows (Not recommended)