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  2. RPG400-L
  3. May 2021

Re: Retrieved record on a chain - file allows duplicate keys

On Wed, May 12, 2021 at 10:30 AM Jeff Crosby <jlcrosby@xxxxxxxxxxxxxxxx> wrote:

Curiosity question.

Suppose a file allows duplicate keys and there are 2 key fields.

If I do a Chain to this file and there are multiple matching records, will
I _always_ get the same record? Like (maybe) the one with the lowest RRN?
Or might it be different from 1 Chain to the next?

You probably already know that from a "pure" database perspective, the
answer is "you should always assume that you could get either record,
and program accordingly".

This is one of those "implementation details" that you're not supposed
to rely on.

I can understand the curiosity though. (I wonder if it's already been
answered in the archives; and even if so, whether the answer then is
the same as the answer now.)

John Y.

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