f73f5600__PDW__and_ROLAP___ORAYLIS_Blog__ly_available_to_the_end_users_
[LOW LATENCY] SUPPORTS LARGE DIMENSIONS
Large dimensions (with many million rows) are difficult to handle for MOLAP SSAS. Processing takes a long time and query performance may go down. But ROLAP works well with large dimensions.
Parallel Data Warehouse (PDW) and ROLAP « ORAYLIS Blog
No need to process MOLAP partitions: low latency (data in the relational data warehouse tables are immediately available to the end users)