Re: Demo: Db For Dummies

From: Neo <neo55592_at_hotmail.com>
Date: 16 Nov 2004 08:59:53 -0800
Message-ID: <4b45d3ad.0411160859.627329cc_at_posting.google.com>

> what is the purpose of these posts?

To demo that XDb2 is for Dummies. While the XDb2 scripts appears simple enough for dummies, it creates the equivalent of the following RM schema (actually it further normalizes the strings in the name columns of various tables, and then normalizes the symbols across all strings). I have used "->" notation instead of ID values to make it easier to follow. Not that RM can't, but if you're unable to post RM's equivalent (normalized/NULL-less) script/queries, then XDb2 might be for you :)

T_Person
name skin hair

----  --------------  ----
john  ->black         ->red,blue
mary  ->white,smooth  ->red,silky,smooth

T_Skin
ID

---

black
white,smooth

T_SkinColor (each skin can have any number of colors)

skin            color
----            ------


->black         ->black

->white,smooth ->white

T_SkinTexture (each skin can have any number of textures) skin texture
------------ --------
->white,smooth ->smooth

T_Hair
ID

---

red,blue
red,silky,smooth

T_HairColor (each hair can have any number of colors)

hair                color
------------------  -------


->red,blue          ->red

->red,blue          ->blue

->red,silky,smooth ->red

T_HairTexture (each hair can have any number of textures)

hair                 texture
------------------   -----

->red,silky,smooth ->silky
->red,silky,smooth ->smooth

T_Color
name

---

red
blue
black
white

T_Texture
name

---

smooth
silky

For something more challenging try posting RM's equivalent script/queries for the example post in thread titled "Demo: John, Mary and R2D2" or at www.xdb2.com/example/ex113.asp Received on Tue Nov 16 2004 - 17:59:53 CET