Re: FW: update files

[Jim Langston <jlangston@xxxxxxxxxxxxxxxx>]

FMyFile   UP   E               DISK

C             If           DType = 'JRNL' And DDStat = 'A'
C             Eval       DDstat = 'X'
C             Update  MyFile01

Assuming: file name is MyFile and record layout is MyFile01
That will do it for you.  This will read through every record in
MyFile and update as per your specs.  This is not very efficient,
however, as it does have to read through every record.  It does
this because the file is opened as the Primary file, and uses the
RPG cycle.

This program, however, should be perfectly fine for a one time
thing, and is normally how I do it.  For something that would run
every day, or something users would use, I would probably make
it a lot more efficient so it runs faster, doesn't have to read the
entire file, and doesn't take up as much CPU cycles.

If you have a key you can look for, you can do it faster.  Say,
perhaps, that your key was DType and DDStat (okay, we know
they're not, but...) then you could do something like this:

FMyFile   UF    E                          DISK

D MyKeyStat     S                   4
D MyKeyType   S                   1

C                    Eval    MyKeyType = 'JRNL'
C                    Eval    MyKeyStat = 'A'
C    MyKey    Setll    MyFile01
C                    Read
MyFile01                                                99
C                    DoW  DDType = 'JRNL' And DDStat = 'A' And
C                               NOT *IN99
C                    Eval     DDStat = 'X'
C                    Update Myfile01
C                    EndDo
C
C                    Eval    *INLR = *ON

C    *INZSR   BegSR
C
C     MyKey    KList
C                     KFld           MyKeyType
C                     KFld           MyKeyStat

There is some way to use Read (E) and check for %EOF, but
as I'm on V3R7M0 I am not really familiar with this.

Also, I typed this code in Netscape, so the spacing is off, and I
may have missed a few things on the file specs and such, but you
should get the general idea.

Regards,

Jim Langston

Art Baker wrote:

> Hello,
>         I looking to update a data file with RPG. Normally I've been using
> UPDDTA and changing the records, when required, but in this case there is
> over 900 records that needed to be updated. My question is which command to
> use, SETLL, READE or CHAIN. There are two things to look for in this file,
> DTYPE
> and DDSTAT. The DTYPE to look for is JRNL and the DDSTAT to look for is 'A'.
> Both JRNL and 'A' need to be true then, change the 'A' to an 'X'.
> Thanks for any advice,
> Art

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