Re: Another JDBC (and by extension, JDBCR4) meta-data retrieval question

On 05 Apr 2013 10:13, John Yeung wrote:

On Fri, Apr 5, 2013 at 11:50 AM, James H. H. Lampert wrote:

On preferred display decimal places, there appears to be no such
animal among the columns of SYSCOLUMNS, and so the answer would
seem to be the same as the answer on relative record number: "That
concept is foreign to SQL." At any rate, it's not a big deal, by
any means.

The concept is foreign to floats. I am trying to decipher what it
even means to have "preferred display" decimal places.

Let's see. After a little bit of experimentation, it looks like the
number of decimal places in the DDS is a hard specification. It's
not a *preferred* anything: you WILL get that many decimal places
DISPLAYED. Then you have to do the usual adjustment with the stuff
that comes after the 'E'.

<<SNIP>>

I presume the /displayed/ results are giving a false impression. What interface was being used to draw that conclusion was unstated, but presumably it was likely either a Display File or the Query/400 report writer; DFU as I recall, does not have support for Float.

Depending on the interface used to /display/ the effects of the specification, the results can change; i.e. not all interfaces will present the human-readable form of the floating point representation with the specified number of decimal digits and decimal digits after the decimal point. The scale as specified in the DDS source [as the "Decimal Positions"] is indeed\actually just a preference offered to those interfaces that would honor the specification.

The only specification of any real merit is the Floating Point Precision; i.e. either FLTPCN(*DOUBLE) or FLTPCN(*SINGLE) specified in the "Functions" to further describe the data-type F=Float.