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Re: Rank taxonomy (was Re: Cladism (akin to masochism))
>> Cool. Now the question is, are the names just put into a list? I.e. you
>>just have a column of names going from the species all the way back to that
>>first blue-green algae?
>> is going to be damn difficult to represent in a relational database......
>Actually its fairly easy. Ages ago (before I knew anything about
>cladistics), I started to set up a database of dinosaur clasifications.
>I started out setting up by tables for class, subclass, order, suborder,
>infraorder, etc. This quickly became unworkable as new levels kept
>appearing, while there were lots of species which skipped levels.
>I then redesigned the database to just use one table which was something like:
> | Node No |<--+
> | Name | |
> | Level | |
> | Parent No |---+
> | (other fields |
>This was using linnean taxonomy so the level field would contain "class",
>"order" or whatever. By the sound of things, this field could be left out in
>a caldistic database.
>I'm not sure if the above is very coherent (its very late and I should be in
>bed), so I'll give an example of your dinosaur (throwing in one or two extra
> Node No Name Parent No
> 1 Dinosauria NULL
> 2 Saurischia 1
> 3 Ornithaschia 1
> 4 Theropoda 2
> 5 Saurapodamorpha 2
> 6 Tetanurae 4
> 7 Coelurosauria 6
> 8 Maniraptora 7
> 9 Deinonychosauria 8
> 10 Deinonychus 9
> 11 Dromaeosaurus 9
>Please forgive any spelling (or other) mistakes. As I say, its late.
Looks like I'll adopt this way of doing things, although I'm probably not
going to use node numbers (IF I can get MS-Access to set up a cascading
referential integrity constraint between two fields in the same table). Thanks.
The problem now becomes pulling all the clades for a single animal from
top to bottom. Recursive joins of unknown number can't be done in SQL. May
have to write a C program to do it (ugh).
** "A warp core breach is imminent? ** "Those who trade a little freedom **
** This calls for the handyman's secret ** for a little security will soon **
** weapon, duct tape." --- Red Green, ** find that they have none of **
** Chief Engineer, U.S.S. Voyager ** either." --- Jeff Poling **