3 ms·
Col-based storage is for usual tables, DW don't need that because all the stuff is pre-joined except for the dimension tables. The dimension tables are tiny II
by zasdffaa 4y ago
Col-based storage is for usual tables, DW don't need that because all the stuff is pre-joined except for the dimension tables.
The dimension tables are tiny IIRC, and there should (?) be only one fact table. You don't join between fact tables anyway (do you?)
I feel you may be mixing up a few things but it's not my strong point here.
- juancn 4y agoYeah, I may have messed the terminology here, depending on the dataset, the dimension tables can be close to the fact table in cardinality, for true flexibility, it degenerates into a fact table with just a record id and dimension tables with a FK to the fact table and a single column. If the DB is a true columnar store, there's no need to do that, but most are record based.