Re: Indexed PF vs. LF performance

I always thought the source of the practice was index corruption. If
an index got corrupted on a LF, you could just delete and recreate but
if you got a corrupted index in a PF, you had to delete the PF and all
the logicals and rebuild.

It was something I remember happening on the System 38 and some in the
AS/400 days but has not been a problem for many, many years.

On Tue, Jul 31, 2012 at 7:30 AM, Booth Martin <booth@xxxxxxxxxxxx> wrote:

Oh gosh, I wasn't trying to defend a practice. Only to explain the
source of it. I apologize if it came out in any other way.

I totally agree with what you say and have keyed nearly all files for
years.


On 7/31/2012 8:15 AM, rob@xxxxxxxxx wrote:

I realize you're just trying to come up with an example so I'll throw out
the argument that keying by a person's name is silly (for the reason you
gave).

Let's say I accept that you couldn't change a PF key (many decades ago).
Well, you should have stopped there. Because when you started on about
child files you lost me. It's not like people used Referential Integrity
constraints years ago. It was easy to delete a parent and leave all those
orphans. How did not keying the PF help? Actually it's easier nowadays
to do this. You can set up the foreign key constraints to "cascade". So
if Miss A becomes Miss B it would cascade the key change down through all
the child files. Back in troglodyte times wouldn't you have had to write
a program to cascade that key change down through the children regardless
of whether or not the key was on the PF or in a LF?


Rob Berendt

--
Booth Martin
802-461-5349
http://www.martinvt.com
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