Re: perfm of Date\Time\Timestamp

On 2011/7/13 5:25 PM, CRPence wrote:

...
As I recall the Date\Time support in the languages had some performance
issues due to implementation choices. I recall also that [a couple
releases] later some changes were made to improve against that original
implementation [perhaps only in the RPG HLL?]; something to do with
utilization of external-form [visual presentation formats] versus
internal-form [integer data] which required conversion from the former
to the latter before doing calculations, and then the reverse conversion
[to external form] for writing to the database. The original
implementation in the database as I understood, was chosen to fit nicer
with both the interface to and the [original design and] implementation
of, the HLLs. I believe part of the changes to improve performance may
have been via exposing database record buffers to an HLL [perhaps only
RPG updated to take advantage] with date data in internal-form versus
external-form for read, and similarly enabling the record buffer from
the HLL to contain internal-form versus external-form for write.

Chuck, the RPG compiler and runtime only work with date data in external-form. The runtime uses MI functions to do any calculations involving dates, including assignments. I believe those MI functions transform to internal form before doing the actual work, and then back to external form for the returned value.