--- Peter Brawley <[EMAIL PROTECTED]> wrote: "As you note, the names [of animal taxons] aren't guaranteed to be unique, or to stay the same . . . > 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 wanted to follow up on this. I can easily substitute integers from my primary key for names, but how do I substitute them for parents? For example: ID | NAME | PARENT 10 | Canidae | Carnivora 11 | Canis | Canidae 12 | Vulpes |Canidae I can easily replace Canis with 11, Vulpes with 12. But they both have the same family - Canidae, which translates as 10. I could create a new field and manually, like this: ID | NAME | PARENT | PARENTID 10 | Canidae | Carnivora | 9 11 | Canis | Canidae | 10 12 | Vulpes |Canidae | 10 But if I add or delete a row, the numerals in my primary key will change, messing up the values in PARENTID. Along similar lines, I have another question... Consider the database table code below, which displays animal names (representing all taxonomic heirarchies) in a child-parent relationship: ID | NAME | PARENT 1 | Mammalia | (NULL) 2 | Carnivora | Mammalia 3 | Canidae | Carnivora 4 | Canis | Canidae 5 | leo | Canis 6 | Felidae | Carnivora 7 | Panthera | Felidae 8 | leo | Panthera Rows 5 and 8 represent identical species names, leo. If I type http://geozoo/stacks/leo/ into my browser, it defaults to Mammalia > Carnivora > Canidae > Canis > leo, rather than the lion, Mammalia > Carnivora > Felidae > Panthera > leo So I need a way to distinguish one leo from the other. Would it be possible to somehow combine my auto-incrementing primary key with the field Name, converting leo / leo to 5leo / 8leo? There are two things I'd have to deal with... 1. I'd need to weed the numerals out of the display, which should look like this... <a href="http://geozoo/stacks/leo/";>leo</a> not this... <a href="http://geozoo/stacks/8leo/";>8leo</a> 2. The numerals would have to be fluid, as I will be adding and deleting rows. Thus, the lion could be 8leo one day and 9leo the next. I can take this to a PHP forum to learn how to implement it. But I thought someone on this forum might tell me if it can be done in the first place. Thanks. __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
