Data engineering·Cost, layout and query performance
the second person to run the identical query got the answer instantly and was charged nothing.
Result cache
Also calledquery result cache, result reuse
Reusing a previously computed result for a byte-identical query when the underlying data has not changed. It makes repeated dashboard loads nearly free and it makes benchmarking treacherous, because the second run of anything is not measuring what you think. Its invalidation is coarse — any write to a referenced table drops it — so on frequently updated tables it does much less than people assume.