CREATE TYPE public.angle_vectors AS (x double precision, y double precision); COMMENT ON TYPE public.angle_vectors IS 'This type holds the x (sine) and y (cosine) components of angle(s).';
How can I protect this function so that NULL is returned whenever *all* input rows are NULL?
Thanks for any feedback,
Going from memory here...
You don't "protect" anything. angle_vectors_stddev_yamartino needs to check whether its input array only contains null and, if so, return null.
AFAIK there is no built-in way to check for only-null since "null = ALL(...)" doesn't work and you cannot say "IS NULL ALL(...)"
