RE: RPG IV program - comments requested

The code itself looks fine but a comment on how the program operates.  The
program reads through the whole file to update only a subset of records.
Depending on the number of records in the file this could be very
inefficient.  It would be better to create a logical file keyed by BSXTRL
and then use Trailer to SETLL and then use READE to only read the records
from the file that you need to update.  We always try and avoid reading
through the entire file unless we are doing something to all (or most) of
the records.  If a program reads all the records in a file then it's
performance will get worse as the file contains more records. 

Scott Mildenberger

> -----Original Message-----
> From: Jim Langston [SMTP:jlangston@conexfreight.com]
> Sent: Friday, September 24, 1999 9:39 AM
> To:   RPG400-L@midrange.com
> Subject:      RPG IV program - comments requested
> 
> This is a small update utility I just created for one of my users.  All
> it does is
> goes through a file and changes one field (BSSCAC) when another filed is
> 
> equal to an input value (BSXTRL).
> 
> There are two input parameters, Trailer and SCACCode.  Trailer is the
> search
> criteria.
> 
> I would request critiquing of this program.  That is, I am using D specs
> to declare
> my variables, I am using a PLIST to declare my entry parameters and I am
> using
> the RPG Cycle to cycle through all my records.
> 
> Since I am just starting to program in RPGLE I do not want to get any
> bad habits
> started now.  I would rather start of on the right foot.
> 
> So I guess I am asking, if you were to write this same program, is this
> the way you
> would code it?
> 
> Regards,
> 
> Jim Langston
> 
>      FBSSHIPX   UP   E             DISK
> 
>      DTrailer          S             10A
>      DSCACCode         S              4A
> 
>      C                   IF        Trailer = BSXTRL
>      C                   EVAL      BSSCAC = SCACCode
>      C                   UPDATE    BSSHIPX1
>      C                   ENDIF
> 
>       *******************************
>       *** Set up Entry Parameters ***
>       *******************************
>      C     *INZSR        BEGSR
>      C
>      C     *ENTRY        PLIST
>      C                   PARM                    Trailer
>      C                   PARM                    SCACCode
>      C
>      C                   ENDSR
> 
> 
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