Thoughts on manual database design?
billdegnan at gmail.com
Fri Oct 2 00:04:21 CDT 2015
Coming up with a schema that works with multiple manufacturers is the big
On Thu, Oct 1, 2015 at 6:01 PM, Jay Jaeger <cube1 at charter.net> wrote:
> On 9/25/2015 4:03 PM, mark at markesystems.com wrote:
> >>> Not sure why you have VARCHARs for primary keys, why not use the
> >>> conventional auto-increment int so you can dispense with
> >>> the LastGeneratedArtifactID table.
> >> Because my artifact ID's are not always just numbers. In some cases
> >> they may already be marked on an artifact (though typically not for
> >> manuals - but this is just the first of a set of such projects, and they
> >> *are* marked on many of my computer boards).
> For anyone who might care, today I decided to move to an auto-increment
> key on the Manual table, and then use that key in the Manual_Artifact,
> Manual_File and Manual_Machines tables. (But not the ArtifactID ;) ).
> It was an outgrowth of doing some data clean up and realizing that a
> manual from one manufacturer was sometimes related to a machine by a
> different manufacturer (e.g., ABLE computer boards in Digital Equipment
> machines). I was going to sometimes end up with two manufacturers in
> the Manual_Machines table, which was apt to get confusing over time.
> So I will now have a Manual_MFG column, which is used only in the Manual
> table, and a Machine_MFG column, used only in the Manual_Machine table.
> A new Manual_Key will be used in place of the Machine_MFG:Manual_Number
> pair I had been using all over the place.
> I still have to finish the model, and will update the PDF I put on my
> website at some point in the next day or so.
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