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

Thanks for the link. That's for DDS created files and mine are all DDL
created, but I assume there is some DDL equivalent.

When we write a credit, I have a program that checks that we're not
crediting an amount greater than the sell amount. Once in a blue moon, a
customer may have the same item on a single invoice more than once. This
is very rare. Such as ordering a full case and a partial case, which just
happened recently. We wrote a credit on the full case as it was ordered in
error. My program retrieved the partial case from sales history and issued
the warning.

I'm going to fix that with an SQL Select sum(sales), but it just got me
curious.

Thanks again.


On Wed, May 12, 2021 at 10:51 AM mlazarus <mlazarus@xxxxxxxxxxxx> wrote:

Jeff,

The short answer is that it's not guaranteed, unless you specify a
"helper" keyword, such as FIFO, LIFO, etc.

See:
https://www.ibm.com/docs/en/i/7.3?topic=files-arranging-duplicate-keys
for some rules.

-mark


On 5/12/2021 10:30 AM, Jeff Crosby 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?

Thanks.

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