Re: Tables and PFs

Dennis,

The objects are not identical. If you create a physical file with DDS,
its properties are different than those of a SQL created table. Even
if you add a field with ALTER TABLE, it remains a PF. A numeric field
can get written with invalid data.

Now, if you create a table (physical file, as opposed to a logical
file or an index), there is no way you can write invalid data on it,
even using CPYF FMTOPT(*NOCHK).

As far as I understood (and my limited English knowledge may get me in
problems here), the OP did not ask what to call these things, but how
to explain the difference:

************************
Is there a simple way to explain the difference between a table and a
physical file a part from one is created by SQL and the other with
DDS?
Should it bug me when a coworker says table but means a PF? It does
and I'm not sure why.
************************

A nice feature of the IBM i is that it allows the use of SQL tables
and PFs in an almost indistinct way. That does not mean they are the
same (you can check it with the DSPFD command)

BTW, the "IBM Certified Systems Expert - eServer i5 iSeries"
certification is not related to DB2. Moreover, that line in my
signature does not (unfortunately) make me an expert in everything
related to the i5/iSeries/i world (and it is a little bit outdated, to
boot). Mostly, it is a holdover from the times I worked for a BP here
in Venezuela. They insisted we wrote our most relevant certification
in our e-mail’s signatures (they did pay for them; after all, those
things are quite expensive for us).

Best Regards,


Luis Rodriguez
IBM Certified Systems Expert — eServer i5 iSeries



On Tue, Jan 12, 2010 at 12:00 PM, Dennis Lovelady <iseries@xxxxxxxxxxxx> wrote:

I suppose that you could explain that a table is a physical file
create with SQL, that has some particular properties of its own.
e.g.., the data is verified BEFORE it gets written, opposed to a DDS
PF, where the data is verified at read time...

Amazing!  Who comes up with these ideas?  Certain not an ...

IBM Certified Systems Expert - eServer i5 iSeries

... I hope.

Dennis Lovelady
http://www.linkedin.com/in/dennislovelady
--
"We do not stop playing because we are old.  We grow old because we stop
playing."
       -- Anon



--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
To post a message email: MIDRANGE-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/midrange-l.