RE: Tables and PFs

["Evan Harris" <spanner@xxxxxxxxxx>]

Hi Chuck

I don't disagree with anything you say here, but the term Physical File only
has meaning in a conversation about the iSeries. In that case, and where
warranted by all means be specific and draw the distinction - I'd do the
same.

I think without knowing the conversation the OP was referring to then
everyone who has posted has been correct - it would help to know the context
of the usage to determine what level of detail would have been appropriate.

Regards
Evan Harris


-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx
[mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of CRPence
Sent: Thursday, 14 January 2010 7:03 p.m.
To: midrange-l@xxxxxxxxxxxx
Subject: Re: Tables and PFs

   Just as the word /table/ used in the program can be "better 
termed" as a e.g. /lookup table/, the /table/ created by SQL can be 
better termed as a SQL TABLE.  In either case, a somewhat generic 
term "table" is replaced with a more specific term, in order to 
avoid confusion.

   I tend to refer to a DDS created database physical file as either 
a PF, or a physical file, and where logical versus physical is not a 
distinction of interest to be noted, then as either database file or 
[written as] "database *FILE".  I will generally add a reference to 
the DDS as source [e.g. DDS PF] or the CRTPF command to clarify 
specifically when an SQL TABLE does not make a satisfactory database 
physical file for the scenario, or explicitly qualify as SQL and\or 
DDL for the inverse case.  Cases do exist for which using one versus 
the other is a requirement for a particular implementation, so being 
clear\specific may be important; i.e. the _distinction_ can be 
_consequential_, so why not just be accurate.?  Is anything less 
expected for the general term "file" on many other OS whereby the 
nomenclature such as PDF, CSV, EXEcutable, etc. is used to denote 
specifically what type of file is being discussed?

Regards, Chuck

Evan Harris wrote:
> No, there really isn't; a PF on the iSeries is basically what the
> rest of the IT world else calls a table. The way I look at it is:
>
> - A table is a thing that contains rows and columns and is part
> of a database
> - A file is a thing that lives in the file system
> - The database will almost certainly live within the file system
> so the distinction is important
>
> As to your tables from the parameter file they would be better
> termed lookup tables or even hashes.
>
> The semantics of what constitutes a table vs. a physical file on
> the iSeries is indistinguishable and inconsequential to the rest
> of the world.
>
> It shouldn't bug you that he says this, it's IT Jargon as opposed
> to an iSeries sub-dialect.
>
> David FOXWELL
> > 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.