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I don't disagree but I think in practice you're probably dealing with a single user at a time when working with orders. A query that referenced n users plus the
by eweise 8y ago
I don't disagree but I think in practice you're probably dealing with a single user at a time when working with orders. A query that referenced n users plus their orders is probably a reporting type query that could be supported in a data warehouse where all the tables could be joined together.
- badestrand 8y ago> query that referenced n users plus their orders is probably a reporting type query No, there are enough other valid cases, e.g. display last customers and their orders or some simple "others have also bought". In practice you will need to join a lot spontaniously and can not just defer that to a data warehouse.
- scarejunba 8y agoMost stores of large scale do not run online calculation or modeling for “others also bought”. It’s usually offline.
- zaarn 8y ago"Show content your friends liked" is an easy example where you want an in database join, in userspace this operation would be incredibly slow.