Wow, now we have four ways of doing the same job But still the one question which of the four versions does the job the fastest? Or could their speed be neglected since the looping through all sub-pages would take the biggest chunk time-wise? And another thought: Once the collection is fetched, does the speed of a foreach-loop differ for the different ways of building the collection?
They are all equally fast since they are doing their calculations based on an in-memory list of pages (this also applies to operations on the newly built collection). It doesn’t matter at all and only depends on what fetching method you prefer/need.
I recommend page('blog') though, it’s the shortest and easiest to understand.