On 12/5/22 18:56, David G. Johnston wrote:
Also, maybe we should have any_value do something like compute a 50/50 chance that any new value seen replaces the existing chosen value, instead of simply returning the first value all the time. Maybe even prohibit the first value from being chosen so long as a second value appears.
The spec says the result is implementation-dependent meaning we don't even need to document how it is obtained, but surely behavior like this would preclude future optimizations like the ones I mentioned?
I once wrote a random_agg() for a training course that used reservoir sampling to get an evenly distributed value from the inputs. Something like that seems to be what you are looking for here. I don't see the use case for adding it to core, though.
The use case for ANY_VALUE is compliance with the standard. -- Vik Fearing
