RE: Separation of Presentation, BL, and I/O Tiers -- RPG400-L

Nelson,

I believe that if you define a MODS or ARRAY as BASED, No storage is used
until you allocate the number of bytes required to the pointer. The only
thing that gets me is that if you define an array as based and dimension it
to 32767 elements, if you only allocate enough memory for 10 elements the
%elem BIF still returns 32767. I wish there were a way to determine how
many actual elements were allocated. Because of the memory allocation
blocking, you couldn't get exact but you could get close.

Just my 2 cents,


Mark


Mark Walter
Sr. Programmer/Analyst
Hanover Wire Cloth a div of CCX, Inc.
mwalter@hanoverwire.com
http://www.hanoverwire.com
717.637.3795 Ext.3040



                    "Smith, Nelson"
                    <NSmith@lincare.c        To:     "'rpg400-l@midrange.com'" 
<rpg400-l@midrange.com>
                    om>                      cc:
                    Sent by:                 Subject:     RE: Separation of 
Presentation, BL, and I/O Tiers
                    rpg400-l-admin@mi
                    drange.com


                    04/10/02 03:23 PM
                    Please respond to
                    rpg400-l






If you have to define it at the maximum occurs, what does being dynamic buy
you?  Would you immediately go in at program startup and resize it back
down
to a reasonable number?  Would that be the benefit?

You say "as for an array".  I thought I had seen examples of people
starting
off with a 100 element array and then resizing it to 200?  You can't do
that?

The end result I'd like to get to is to have an I/O routine that gets a
bunch of records (by RPG, SQL, Stored procedure, whatever), sizes an array
or ds to hold them based on the number it found, then just return a pointer
to the structure along with the number of records contained in it.

So, would the I/O module have to declare the MODS at the maximum Occurs,
get
the records, then reallocate the MODS back down to the actual number of
records retrieved, then return to the calling program?  Then, the calling
program would have to do the same thing, start off with a maximum size ds,
and reallocate it down after it got the pointer back from the I/O module?

Is that the scenario? Would there be any performance issues here, when an
application may be doing this for hundreds of files?

> -----Original Message-----
> From:         Jon Paris [SMTP:Jon.Paris@Partner400.com]
> Sent:         Wednesday, April 10, 2002 2:51 PM
> To:           rpg400-l@midrange.com
> Subject:           Separation of Presentation, BL, and I/O Tiers
>
>  >> I've seen several posters saying they could, but have seen no
examples
> of that, yet.
>
> MODS can be based (and therefore dynamically sized) just as arrays can.
> The
> limitation (as for an array) is that you must define the number of
> occurrences as the largest number you will ever need.  I like the
> technique
> because it has the added advantage that you can have multiple definitions
> of
> the DS and map them to individual occurrences of the MODS so you simply
> directly compare multiple occurrences.
>
> You can also use things like the C qsort and bsearch routines to sort and
> search the MODS.
>
> Jon Paris
> Partner400
>
>
> _______________________________________________
> This is the RPG programming on the AS400 / iSeries (RPG400-L) mailing
list
> To post a message email: RPG400-L@midrange.com
> To subscribe, unsubscribe, or change list options,
> visit: http://lists.midrange.com/cgi-bin/listinfo/rpg400-l
> or email: RPG400-L-request@midrange.com
> Before posting, please take a moment to review the archives
> at http://archive.midrange.com/rpg400-l.


************************************************************************************************************************************************************************************************************

This message originates from Lincare Holdings Inc. It contains information
which maybe confidential or privileged and is intended only for the
individual or entity named above.
It is prohibited for anyone else to disclose, copy, distribute or use the
contents of this message.
All personal messages express views solely of the sender, which are not to
be attributed to Lincare Holdings Inc., and may not be copied or
distributed without this disclaimer.
If you received this message in error, please notify us immediately at
MailAdmin@lincare.com or (800) 284-2006.
************************************************************************************************************************************************************************************************************


_______________________________________________
This is the RPG programming on the AS400 / iSeries (RPG400-L) mailing list
To post a message email: RPG400-L@midrange.com
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/cgi-bin/listinfo/rpg400-l
or email: RPG400-L-request@midrange.com
Before posting, please take a moment to review the archives
at http://archive.midrange.com/rpg400-l.