Re: Would it be a reasonable to ask IBM's programmersto write a%sortsfl(sfl: column)

Once you write a record to a subfile, that record belongs to the *FILE
object. So manipulating that record (and all the records in the subfile)
would require your program communicating something to the display file.
As an example, highlighting a field on a record in a subfile requires a
WRITE operation from your program to the display file indicating the
subfile record number and the indicator to set to highlight the field as
declared in your file definition DDS.

So the only way to sort an already written subfile would be to declare a
sort column, perhaps qualified with an indicator, in your DDS (currently
unsupported), display the subfile, and then write an override to the
display file. Providing such a feature would be the purview of the folks
who manage the display file code, not those who do compilers.

Remember, display files can be used in any of the i languages: RPG, C,
COBOL, Pascal, PL1, ... and the same features would be available there.


-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx
[mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Booth Martin
Sent: Tuesday, December 08, 2009 3:44 PM
To: Midrange Systems Technical Discussion
Subject: Re: Would it be a reasonable to ask IBM's programmersto write
a%sortsfl(sfl: column)

Thats the part I did not understand.
The subfile is all ready written. It is a known block of data. There's
no need for any under the covers work or any connection to the data;
just process the existing data in the existing subfile. Sort the first
request ascending and any following requests in the opposite order.

Frankly it surprised me that someone didn't say this is a lunch time
sport for the people that are really good at %bifs.




DeLong, Eric wrote:

Hmm, maybe just allow an SQL statement to be associated with the SFL,
and allow OS400 to manage the paging through the result set?
-Eric DeLong