I would expect numbers in the range -2147483648 to +2147483647 to be accepted
(the size of an integer), and then there’s a separate field for storing whether
things are shifted to the left or right. I’ve no experience or theoretical
knowledge confirming this, but your examples would fit such a description.
Hence, I would guess NUMERIC to default to NUMERIC(9, 0).
I've confirmed that
SELECT CAST('2147483647' as numeric) FROM RDB$DATABASE
SELECT CAST('2147483647' as numeric(9,0) FROM RDB$DATABASE
both are accepted, whereas
SELECT CAST('2147483648' as numeric) FROM RDB$DATABASE
SELECT CAST('2147483648' as numeric(9,0) FROM RDB$DATABASE
are rejected.
HTH,
Set
