with from_a as (
	select uuid, api_utc, version
	from A
), from_b as (
	select levuuid, event_utc
	from B
), build_c as (
	select
		uuid, levuuid,
		abs(api_utc - event_utc) as time_diff,
		version
	from
		from_a
	full outer join
		from_b
	on from_a.uuid = from_b.levuuid
), ordered_build_c as (
	select *, row_number over (partition by coalesce(uuid, levuuid)) order by time_diff as rank_number
)
select
	coalesce(uuid, levuuid),
	version
from
	ordered_build_c
where rank_number = 1