Re: maximum digits for NUMERIC

On Fri, Apr 01, 2011 at 03:52:22AM -0400, Noah Misch wrote:

> NumericLong has a 14-bit count of decimal digits for the dscale, giving that
> fractional digit limit.  It stores the weight as a 16-bit signed count of
> base-10000 "digits" after the first.  For example, 10^4-1 has weight 0, 10^4
> through 10^8 - 1 have weight 1, 10^8 has weight 2, etc.  For purposes of hitting
> the positive limit, we have 15 bits of weight.  Therefore, it can represent up
> to 2^15 * 4 = 2^17 digits.

OK; thanks also for the explaination.

>
> > --- a/doc/src/sgml/datatype.sgml
> > +++ b/doc/src/sgml/datatype.sgml
>
> There's a table further up on this page that lists of the range of each type,
> with "no limit" listed for numeric.  It could use an update noting with the
> supported extremes and fractional digit limit.

OK.

Please find attached v2 of the numeric-doc patch, which takes into
account your remarks. In particular, numeric limits are now correct
and documented only in that table.

Best regards,
Dr. Gianni Ciolli - 2ndQuadrant Italia
PostgreSQL Training, Services and Support
gianni.ciolli@2ndquadrant.it | www.2ndquadrant.it