Re: Recursive Arrays 101

On 10/26/2015 08:32 AM, Rob Sargent wrote:
> On 10/26/2015 09:22 AM, Adrian Klaver wrote:
>> On 10/26/2015 08:12 AM, Rob Sargent wrote:
>>> On 10/26/2015 08:43 AM, Jim Nasby wrote:
>>>> On 10/25/15 8:10 PM, David Blomstrom wrote:
>>>>> @ Adrian Klaver: Oh, so you're suggesting I make separate tables for
>>>>> kingdoms, classes and on down to species. I'll research foreign
>>>>> keys and
>>>>> see what I can come up with. I hope I can make separate tables for
>>>>> mammal species, bird species, fish species, etc. There are just so
>>>>> many
>>>>> species - especially fish - the spreadsheets I use to organize them
>>>>> are
>>>>> just about maxed out as it is.
>>>>
>>>> The suggestion is simply to have 7 tables:
>>>>
>>>> CREATE TABLE kingdom(
>>>>   kingdom_id serial PRIMARY KEY
>>>>   , kingdom_name text NOT NULL
>>>>   , ...
>>>> );
>>>> CREATE TABLE phylum(
>>>>   phylum_id serial PRIMARY KEY
>>>>   , kingdom_id int NOT NULL REFERENCES kingdom
>>>>   , ...
>>>> );
>>>> CREATE TABLE class(
>>>> ...
>>>> );
>>>>
>>>> and so-on.
>>> Seems to me that if life boils down to four attributes one would have a
>>> single table with those four attributes on the particular life form.
>>
>> Out of curiosity what are those four attributes? It would have made
>> memorizing all those organisms a lot easier when I was in school:)
>>
> kingdom phylum class genus as attributes in species table.  Talk about
> your "natural key".  The hibernate boys would love it :)

Well in this classification system it would need to be:

kingdom phylum class order family genus

What makes it complicated is that these are just the slots. How
organisms are slotted depends on attributes and there are a lot of them.
This means there is a constant rearrangement in the slotting.

>
>>> Now, the four attributes could be ids into definitional tables but I
>>> suspect the querying will be done string/name so why complicate the
>>> lookups: make the names a foreign key in the defs if necessary.
>>>
>>> Personally I think the recursive structure is the way to go.
>>
> Jtbc, I'm not advocating this structure but it may suit the OP's usage
> patterns.
>
>


--
Adrian Klaver
adrian.klaver@aklaver.com