There are practical applications, eg, 1024-bit keys are fairly common
objects in cryptography these days, and that equates to about 10^308.
I don't really foresee anyone trying to run crypto algorithms with SQL
NUMERIC arithmetic, though ...
2046 bit keys are becoming more common. However, math using these keys
is
usually done modulo a product of two primes and there are ways of
doing the
calculations that are going to be much faster than doing them the way
Postgres does. So it is unlikely that anyone would be using Postgres'
numeric
type to do this in any case.
Nonetheless, the fact that people can think of practical applications
for numbers whose length is easily within a factor of two of the
proposed limitation makes me squeamish about it being shrunk. Also, I
would say the same arguments about doing math with NUMERICs suggest
that saving a few byes in representation is not a big deal. On the few
occasions where I have used NUMERICs, I didn't care about stuff like
that.
For what it's worth.
- John D. Burger
MITRE
