Thoughts on manual database design?

Wed Sep 23 09:17:12 CDT 2015

On 9/23/2015 1:38 AM, steven at malikoff.com wrote:
> Instead of cooking up another completely custom inventory management schema, you might consider adhering to Dublin Core for some more modern
> schema conventions:
> https://en.wikipedia.org/wiki/Dublin_Core

Slightly more useful than MARC, but really it comes down to just a field
naming issue.

Relatively few of my fields are present there:

Title, Publisher, Creator (what I called Machine_MFG), Date (though
their definition is really really vague), identifier (my Manual_Number),

Their type would just be "Text" or "StillImage" for all of my stuff -
not sufficiently specific for my uses.

Subject is only *roughly* equivalent to my Machine table, and would not
do the job I need done with it.

I don't plan on a lengthy description.  No way I am going to enter that
much data.

> 
> For the dbms engine I would use MariaDB over MySql (but with some of the MySQL tool chain) as I prefer code to remain outside the clutches of Oracle:
> https://mariadb.org
> It's a drop-in replacement, runs nicely and the HeidiSQL management client is very useable.
> 

I certainly understand that point of view.  However, that really isn't
an issue for me, and MySQL is presumably better supported by hosting
outfits.

> Also, why are you restricting your field lengths so much? This is the 21st century, you can afford to be a bit more generous on those VARCHARs :)

Probably.  On the other hand, really easy to make them longer, too,
should that prove necessary - this isn't a 100 million row table.  And
the fields are already longer, in most cases, than I would want to
actually display and longer than the fields I currently have - which
have already been lengthened as needed.

> Final thing, are you going for a completely normalised database? (ok, I haven't analysed your schema to any great extent)

THANKS FOR ASKING THAT QUESTION.  Well I thought I had done a decent job
of practical normalization, but clearly missed some things that I
noticed as a result of your question.

First, I certainly should pull out the File and Online fields into a
separate table because as is they could result in
redundancy/inconsistency between multiple copies in my inventory.
Pulling them into a separate table will remove the redundancy, and also
allow for the eventual possibility of multiple online sources for a
given manual.

TABLE File

  Fields:  Machine_MFG(K), Manual_Number(K), OnlineLocation(K)*,
OnlineVersion*, OnlineMD5*.

   (Filename goes away - it is just an instance of "OnlineLocation")

(*) - removed from original Manual table.

Theoretically, I should separate the copies into a separate copy table,
keyed by artifact ID, but it wouldn't really buy me much, as I almost
always store multiple copies of a manual in the same place.  Still it
probably would be the way to go:

TABLE Artifact
   Fields: ArtifactID(K), Location*, Cabinet*, Drawer*, InventoryDate*,
   Missing*, Original*, Incomplete*, Publisher*, Date*

   I think I will add a field "Marked" - Boolean - true if an artifact
   has been marked with its ArtifactID.

   I *might* also yank Publisher and Date into this table.  Have to
   think about that, but with the possibility of multiple printings,
   the Date almost certainly belongs here.  I suppose one could argue
   the same for Publisher.  AH YES!  HP and Apollo - different
   publishers for the exact same manual.
   So, yes, these need to move too.

So now, table Manual just has the following:

   Machine_MFG(K), Manual_Number(K), Title, Type

And I need a relationship table to bind the two together:

TABLE ManaulArtifacts

   ArtifactID(K), Machine_MFG, Manual_Number

> 
> Steve.
> 
> 
> ---------------------------- Original Message ----------------------------
> Subject: Thoughts on manual database design?
> From:    "Jay Jaeger" <cube1 at charter.net>
> Date:    Wed, September 23, 2015 12:00 pm
> To:      cctalk at classiccmp.org
> --------------------------------------------------------------------------
> 
>> So, I am looking to convert my old Access database I have used for many
>> years to a MySQL database, with the expectation that I will eventually
>> publish it on a web page for public lookup.
>>
>> Below is my first cut at a database design for it.  I'd be happy for
>> comments and suggestions, to the list or directly.  Note, however, that
>> I don't expect to do this to the same level of complexity and
>> completeness that one might if they were the library of congress, a
>> major university library, etc.  So, some suggestions to generalize may
>> be quietly ignored, even if they would in principle, be the "right
>> thing" according to some criteria or other.
>>
>> This would be used for manuals, per se, print sets, etc.  Quite possibly
>> for books as well.
>>
>> What follows amounts to a data dictionary:
>>
>> Table MANUAL:
>>
>>   This is the primary table of manuals.  Many of the fields will be
>>   available for string and/or pull down search, as appropriate.
>>
>> Machine_MFG:  VARCHAR(32)
>>   The manufacturer of the machine(s) to which the manual applies
>>   Part of unique key.
>>   Pull down search.
>>
>> Manual_Number: VARCHAR(40)
>>   The manual number, including version strings, etc.
>>   In some cases, this may be an SBN or ISBN.
>>   Part of unique key
>>   String search.
>>
>> Artifact_ID: CHAR(16) [format/type still under consideration]
>>   The local identifier for the manual/artifact.
>>   Part of unique key.
>>   Will be generated if none is entered during creation/update.
>>   (Required because I may have more than one copy of a given manual).
>>
>> Publisher: VARCHAR(32)
>>   The publisher of the manual.  (Typically will be the same as the
>>   Machine MFG - but not necessarily always)
>>   May not be NULL.
>>
>> Type: VARCHAR(16)
>>   Manual, Drawing (== printset, schematic, etc.), Book, ...
>>   Pull down search.
>>
>> Original: BOOLEAN
>>   True if an original manual.  False if a copy ("Xerox").
>>
>> Missing: BOOLEAN
>>   True if the manual is missing (i.e., is not where it is supposed to
>> be, and the actual location is not known).
>>
>> Title: VARCHAR(255)
>>   The title of the manual, including any subtitles.
>>   Suggest "; " to separate multiple titles/subtitles
>>   May not be NULL
>>   String search.
>>
>> Incomplete: CHAR(1)
>>   Indicates if the manual is not a complete copy.
>>   NULL indicates the copy is complete.
>>
>> Year: DATE
>>   The year the manual was published / printed / copyrighted.
>>   May be NULL, signifying the date is unknown / not entered.
>>
>> Location: VARCHAR(20)
>>   The general location of the manual in my inventory
>>   May be NULL, signifying the manual is not in my inventory.
>>
>> Cabinet: CHAR(2)
>>   The ID of the cabinet or box in which the manual is stored, if any.
>>   May be NULL, even if the manual is in my inventory.
>>   May not be NULL if Drawer is not NULL.
>>
>> Drawer: CHAR(2)
>>   The ID of the drawer of the cabinet in which the manual is stored,
>>   if any.  May be NULL.
>>
>> Inventory_Date:  DATE
>>   The date that the manual was last inventoried.
>>
>> Filename: VARCHAR(255)
>>   The name of the file which is an image of the manual in my local
>>   file storage.
>>
>> OnlineLocation: VARCHAR(255)
>>   URL of the manual located online (e.g., the bitsavers URL)
>>   May be NULL.  This does NOT mean that the manual is not online.
>>   Of course, this field can become out of date.
>>
>> OnlineVersion: CHAR(1)
>>   = means that the online manual is the same version as this one
>>   > means that there is no equal version online, but there is a
>>     later version
>>   < means there is no equal or later version online, but there is an
>>     earlier version.
>>
>> OnlineMD5: CHAR(32)
>>   MD5 hash of online manual - used to check for moved manuals.  ;)
>>
>>
>> TABLE MachineManual
>>
>> This table cross references manuals to the machine(s) to which they
>> apply.  This list will NOT be guaranteed to be complete.  During inquiry
>> and update, this will be a list of machines with a separator character
>> in between which will not be allowed in Machine_MFG.  During an update,
>> the entire list will be replaced with the first one being flagged as the
>> primary machine.
>>
>> MachineMFG:  (See above).  Part of the unique key for this table.
>> Manual_Number: (See above)  Part of the unique key for this table.
>> Machine:  VARCHAR(16)
>>    One of the machine(s) to which this manual applies.
>>    Part of the unique key for this table.
>> Primary_Machine: BOOLEAN
>>    When true, indicates that this machine should be listed first
>>    in the list of applicable machines.  For a peripheral, this will
>>    typically be the machine for which the peripheral was originally
>>    designed.
>>
>> So a list of machines for an RX01 manual might be:
>>    PDP-11, RX01, RX01, VAX-11
>>
>>
>> TABLE Machines
>>
>> A lookup table of valid machines.  Only column is Machine (See above).
>> Naturally this table will change over time - I anticipate that an update
>> where the updater (me) keys in an "invalid" one will be greeted with
>> some kind of confirmation panel.
>>
>>
>> TABLE Manufacturers
>>
>> A lookup table of valid manufacturers.  Only column is Machine_MFG
>> (See above).  Naturally this table will change over time - I anticipate
>> that an update where the updater (me) keys in an "invalid" one will be
>> greeted with some kind of confirmation panel.
>>
>>
>> Table Types
>>
>> A lookup table of valid Types. Only column is Type (See above)
>>
>> TABLE:  LastGeneratedArtifact
>>
>> The last generated artifact ID - used to assign new artifact numbers
>> when one is not manually entered.  Algorithm TBD.  One column:
>> Artifact_ID (See above)
>>
>>
>> TABLE: Locations
>>
>> A table of valid locations (e.g. Basement, Garage, STORAGE, Unknown, etc.)
>> Used for convenience during data entry.
>>
>>
>> (Once this one is done and running (at least locally), the next one is
>> probably media (tapes, floppies, etc.) which is not too bad, and then
>> machines, cards and parts, which is more complicated for lots of reasons).
>>
>> After those are done (hopefully by the end of the year - I am retired
>> and this will be my primary focus for a while) comes the design for a
>> database for SMS cards and for the IBM 1410 use of SMS cards.
>>
>>
>> JRJ
>>
>>
>>
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> 
> 
> 