Let’s say you have a mostly read-only DB (otherwise things are different). Does it work when the view is insanely big? [i am not an expert at DBs, so my vision

Let’s say you have a mostly read-only DB (otherwise things are different). Does it work when the view is insanely big? [i am not an expert at DBs, so my vision of a big DB might amuse you, but let’s say I have millions of rows to assemble as a view].