Honestly, I would say scorable is a word. It may not be in the major dictionaries, but you can often find it in academic literature:
Using GFP as a Scorable Marker in Walnut Somatic Embryo Transformation
Construct Validity of Free-Response and Machine-Scorable Forms of a Test
...the grader may draw up to 21 additional sample units and apply the criteria in the AIM Foreign Material Manual, Table II, (flavor is a non-scorable factor).
and so on.
However, if you are talking about something that you can score yourself (or which can score itself), then use self-scoring (or self-rating) instead of self-scorable.
(Edit) "Scorable" is fine for a database column, since those don't have to be perfect English anyway. Any who reads it will know what it means.
CanBeScored
orAllowsScoring
. Also, judging from this, it seems like a lot of uses are associated with sports. Is that the context for the program/database that you are developing? – mathewb Oct 26 '18 at 17:19