Actually in their example, no data is processed.
The query compiled to a loop over natural numbers that was optimized by the compiler:
uint64_t x = 0;
for (uint64_t i = 0; i < 1000000000000; ++i)
x += i;
print x;
This loop is completely eliminated by compiler optimizations.
But it does not make much sense to run these queries in SQL :)
