Jim Wallace wrote:
> Below is output from a test program (copying the code from MySQL++) that
> prints out a float with %f and ostringstream with increasing precision.
> You can see 9 is a better value than 7, but higher than 9 doesn't help.
After reading some of this: http://en.wikipedia.org/wiki/Floating_point
...I can see going to 8. The article says "about 7 decimal digits", but
that just means it's between 7 and 8, closer to 7 in this instance.
What I don't understand is why going to 9 helps. If we assume that your
floating point implementation is adhering to the IEEE 754 standard, the
bits just aren't there to do anything significant with more than 8 digits.
As for double, we may not have to change anything: "about 16 digits"
means between 15 and 16, closer to 16.
> I haven't investigated SQLSS will it do
> the same thing?
It uses the same underlying conversion mechanism as the rest of the
library in v3: SQLTypeAdapter.