On Wed, 2025-03-05 at 14:18 +0330, me nefcanto wrote: > That means a solid monolith database. We lose many goodies with that. > As a real-world example, right now we can import a single database > from the production to the development to test and troubleshoot data. Well, can't you import a single schema then? > What if we host all databases on the same server and use FDW. What > happens in that case? Does it return 100 thousand records and join > in the memory? It will do just the same thing. The performance could be better because of the reduced latency. > Because in SQL Server, when you perform a cross-database query > (not cross-server) the performance is extremely good, proving that > it does not return 100 thousand ItemId from Taxonomy.ItemCategories > to join with ProductId. > > Is that the same case with Postgres too, If databases are located > on one server? No, you cannot perform cross-database queries without a foreign data wrapper. I don't see a reason why the statement shouldn't perform as well as in SQL Server if you use schemas instead of databases. Yours, Laurenz Albe
