Re: Sorting records in Physical and Logical files

Ok. Thanks for that clarification. So, am I correct in assuming that if the keys were in the order in the DDS I had defined, when an *RPG* program read them, it would be in the order that the keys were defined in (as long as K was in the F spec)? Is that also true for logicals? That is, the ONLY time the keys are determining the "order" of the records is when they are read through RPG? Then I would expect that if I opened a physical file in Query OR opened any associated logical in Query, the records would display in arrival sequence regardless of how the DDS was defined in either the logical or physical file? If so, that is new information for me.

I thought DDS had broader implications than just in RPG programs.
Pete


Jim Franz wrote:

SQL is trying to be as efficient as possible.
If you don't ask for ORDER BY, then whatever order it returns is
assumed to be ok. Don't assume by rrn either.
In RPGLE it would be same if the "F" specs had no "K"
to indicate keyed access.
Jim Franz

----- Original Message ----- From: "Pete Helgren" <Pete@xxxxxxxxxx>
To: "Midrange Systems Technical Discussion" <midrange-l@xxxxxxxxxxxx>
Sent: Thursday, August 21, 2008 5:26 PM
Subject: Re: Sorting records in Physical and Logical files

In the DDS? I though the point of a logical file was to build an index
that was an alternate to the default sorting sequence of the Physical
file (among other things). Yes, I could issue an ORDER BY using SQL or
OPNQRYF by I though the file had a "natural" sorting order that was set
by the DDS.

So, there is no way to define a physical file using DDS to sort records
in anything other than arrival sequence?

Pete

Alan Shore wrote:

What you are seeing is in fact correct. You have to ORDER BY for the order
you want



Alan Shore
Programmer/Analyst, Direct Response
E:AShore@xxxxxxxxxxx
P:(631) 244-2000 ext. 5019
C:(631) 880-8640
"If you're going through Hell, keep going" - Winston Churchill

midrange-l-bounces@xxxxxxxxxxxx wrote on 08/21/2008 04:43:26 PM:

I thought I understood this but apparently I don't.

I have a physical and logical file with the following specs:

UNIQUE
R FASA809 TEXT('List Workfile')
-------------------------------------------------------
record layout here:
SLWID 6S 0 COLHDG('Absence ID')
SLW# 6S 0 COLHDG('Seq. Number')
SLWSN 9S 0 COLHDG('Sub SSN')

K SLWID
K SLW#

The logical file looks like:

UNIQUE
R FASA809 PFILE(PASA809)

K SLWID
K SLWSN


The physical file has a randomly generated number in field SLW# and
since the keys are SLWID and then SLW# in that order. I would expect the
file to be ordered that way when I open it up in Query or a simple
select with no ordering in SQL. However, the file is always ordered in
arrival sequence. If I read through this file, I see the records in the
order in which they were written in the file. I *expected* them to be
ordered by the key sequence.

What did I miss or misunderstand?

Thanks

Pete

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