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From:David Blomstrom Date:August 24 2005 5:20am
Subject:Re: Treating Two Fields Like One
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--- Peter Brawley <peter.brawley@stripped> wrote:

> David,
> 
>  >1. Some species names are shared by more than one
>  >mammal. For example, there's a marsupial named
>  >Antechinus leo.
> 
>  >2. Species are more properly cited with the name
> of
>  >their parent (genus), so I eventually want my
> species
>  >URL's to look like this:
> 
> <snip>
> 
> As you note, the names aren't guaranteed to be
> unique, or to stay the 
> same either, therefore they won't do as primary
> keys, therefore they 
> won't do as foreign keys. Also our understanding of
> these taxonomic 
> relationships can change even when the names don't,
> and it's considered 
> a design error to make it necessary to edit primary
> keys in order to 
> update database tables.
> 
> One way out is to give every table an
> auto-incrementing integer PK, and 
> use those keys, which will never change, to mark
> parent-child relationships.

I already have an auto-incrementing integer PK, but I
haven't used it in my queries, as I thought I'd need
actual names to work with my scripts. But now that you
mention it, I'm probably mistaken, so I'll give it a
try.

Thanks.



		
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Thread
Treating Two Fields Like OneDavid Blomstrom24 Aug
  • Re: Treating Two Fields Like OneEnrique Sanchez Vela24 Aug
  • Re: Treating Two Fields Like Onedouglass_davis24 Aug
    • Re: Treating Two Fields Like OneDavid Blomstrom24 Aug
      • Re: Treating Two Fields Like Onedouglass_davis24 Aug
        • Re: Treating Two Fields Like OneDavid Blomstrom24 Aug
  • Re: Treating Two Fields Like OnePeter Brawley24 Aug
    • Re: Treating Two Fields Like OneDavid Blomstrom24 Aug
    • Re: Treating Two Fields Like OneDavid Blomstrom24 Aug
      • Re: Treating Two Fields Like OneSGreen24 Aug
        • Re: Treating Two Fields Like OneDavid Blomstrom24 Aug
      • Re: Treating Two Fields Like OnePeter Brawley24 Aug
RE: Treating Two Fields Like OneGordon Bruce24 Aug
Re: Treating Two Fields Like OneDavid Blomstrom25 Aug
  • Re: Treating Two Fields Like Onedouglass_davis25 Aug