• Subject: Re: PF File Definition questions...
  • From: "Nelson C. Smith" <ncsmith@xxxxxxxx>
  • Date: Fri, 15 Oct 1999 17:56:22 -0400

Even if you already have a "primary key" logical, when you go to add
constraints, it will require a primary key constraint on the physical.  It
will share the access path of your logical but there is a very important
Gotcha to watch out for.  If you remove all constraints from the physical,
including the primary key constraint, the system will do just that, even
though there was a logical sharing that access path.  You won't get an error
until you try to use your logical again.  For this reason, our utilities
that remove constraints always leave the primary key constraints alone.

-----Original Message-----
From: Dan Bale <dbale@genfast.com>
To: MIDRANGE-L@midrange.com <MIDRANGE-L@midrange.com>
Date: Friday, October 15, 1999 5:15 PM
Subject: Re: PF File Definition questions...


>
>
>Rob,
>
>>> I am trying to follow database rules.  You cannot do
>>> Referential Integrity on files without a primary key.
>
>Could you please enlighten me on this statement?  When you say "primary
key",
>are you implying that a unique keyed access path must be defined in the
physical
>file?  If so, why not in a logical file?  (Which is what I do.)
>
>- Dan Bale
>
>
>
>
>
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