Re: how to tell if LF is a Joined LF

"RPG400-L" <rpg400-l-bounces@xxxxxxxxxxxx> wrote on 01/30/2018 01:00:02
PM:

----- Message from Jay Vaughn <jeffersonvaughn@xxxxxxxxx> on Tue, 30
Jan 2018 12:07:31 -0500 -----

To:

"RPG programming on the IBM i (AS/400 and iSeries)"

<rpg400-l@xxxxxxxxxxxx>

Subject:

Re: how to tell if LF is a Joined LF

thank you vern - some good insights there.

On Tue, Jan 30, 2018 at 10:26 AM, Vernon Hamberg

<vhamberg@xxxxxxxxxxxxxxx>

wrote:

Hi Jay

I would not expect to see the format level ID in the system catalogs -
those are very strongly tied to SQL, and SQL has no interest in that

level

ID.

I did look at SYSTABLES, where information about the join files would
reside - no format level ID.

Now I have been curious - you can use the DSPFD command to get

everything

you want - you'd run it twice into *OUTFILEs - one run would use
information type *RCDFMT, the other could use *JOIN and get you a list

of

the JOIN specs

A caution - it is risky to directly query the QADB* tables - they

require

elevated authority even to read them, while the SYS* views over them

are

completely usable but don't necessarily pull everything.

One problem especially with QADB* files if you use native RPG I/O is

that

they change, so SQL is the better approach there.

Regards
Vern

Of course the QDFRTVFD API will return pretty much anything and most
everything you might want to know about a file (or table). You have to
wade through the documentation to find where the offset to the information
you want is, but it's very quick and efficient to get information about a
specific file.

Michael Quigley
Computer Services
The Way International