Re: SQL null indicators when not all columns are null capable

On May 9, 2010, at 1:00 PM, rpg400-l-request@xxxxxxxxxxxx wrote:

RPG itself always converts the date value into a character presentation
depending on the date format either specified in the D- or H-specs (or if
neither specified it uses ISO) and reconverts it immediately before writing
into a table. That's why you won't see the binary value even in debugging an
displaying the Hex-Values and that's why RPG may get an overflow when using
date formats with a 2 digit year.

Not quite true Birgitta - although it does appear to work this way. It is not RPG but the underlying system I/O APIs that make the conversion - in other words by the time RPG even sees a record it is already converted to character form. It is true that the H-spec etc. have an impact - but only in determining what the internal format of a date field is. It will be presented in the buffer to RPG in the form that it is specified on the DB. The H-spec entry may cause it to be reconverted as it is moved from the buffer to the field.

RPG presents to the I/O layer a character string for any date being written - it is converted by the system to binary completely separate from the RPG routines. RPG in fact has no way to override this behavior - SQL goes in lower down and obviously has the ability to take the data in raw form.

It is because it is the underlying I/O that does the conversion that you always see a character formatted date in DFU, or for that matter in COBOL or C which simply map their record buffers directly to the system supplied buffer.


Jon Paris

www.Partner400.com
www.SystemiDeveloper.com