is sql really equivalent to grep?
From: pc <magoo_at_pssstoff.org>
Date: Tue, 07 Dec 2004 02:16:05 GMT
Message-ID: <Fn8td.326458$9b.156001_at_edtnps84>
>
> clothing. He wants an article number for each item of clothing.
> However each item of clothing has a size (s/m/l) and a possible range
> of colours. He wants to be able to keep track of the stock for each
> size and colour but he only wants an article number for each style. <<
>
> Design a vector code. Ever see the ISO tire (tyre) sizes? They are a
> three part vector code: <width in cm><material><diameter in inches>,
> so you can have a 155SR15 tire that we know is a steel belted radial
> tire mesuring 155 centimeters wide on a 15" rim.
>
> I'd create a hierarchical item component, probably 3 or 4 digits will
> be enough. Ever seen Dewey Decimal Classification in a library?
>
> 100's = shirts
> ...
> 200's = pants
> 210's = jeans
> 211 = low rise jean
>
> Then you need a size code, but you showed jeans as being S/M/L instead
> of waist/inseam. That makes no sense to me, but that's what you said.
>
> Then you need a color code. Land color numbers or gif and jpg codes
> are very precise. A 2-3 letter alphabetic abbreviation might do as
> well for this application. So ou might have something like:
>
> '211-grn-s' = a small green pair of row rise jeans.
>
> Then you need a validation check; does your SQL have a version of
> grep() or SIMILAR TO predicsates?
>
> CREATE TABLE Inventory
> (sku CHAR(9) NOT NULL PRIMARY KEY
> CHECK (sku SIMILAR TO '[0-9][0-9][0-9]-(grn|blu|wht)-(s|m|l)'),
> ..);
>
> And as you have already noticed, your client is insane not to allow
> all of the attributes in the database in proper columns.
>
>
>
>
> You need to change the validation constraint on the Inventory table to
> allow for a new color code.
Received on Tue Dec 07 2004 - 03:16:05 CET
Date: Tue, 07 Dec 2004 02:16:05 GMT
Message-ID: <Fn8td.326458$9b.156001_at_edtnps84>
a recent exchange makes me wonder if i think so:
--CELKO-- wrote:
>>>I am designing a relational database for a client who sells
>
> clothing. He wants an article number for each item of clothing.
> However each item of clothing has a size (s/m/l) and a possible range
> of colours. He wants to be able to keep track of the stock for each
> size and colour but he only wants an article number for each style. <<
>
> Design a vector code. Ever see the ISO tire (tyre) sizes? They are a
> three part vector code: <width in cm><material><diameter in inches>,
> so you can have a 155SR15 tire that we know is a steel belted radial
> tire mesuring 155 centimeters wide on a 15" rim.
>
> I'd create a hierarchical item component, probably 3 or 4 digits will
> be enough. Ever seen Dewey Decimal Classification in a library?
>
> 100's = shirts
> ...
> 200's = pants
> 210's = jeans
> 211 = low rise jean
>
> Then you need a size code, but you showed jeans as being S/M/L instead
> of waist/inseam. That makes no sense to me, but that's what you said.
>
> Then you need a color code. Land color numbers or gif and jpg codes
> are very precise. A 2-3 letter alphabetic abbreviation might do as
> well for this application. So ou might have something like:
>
> '211-grn-s' = a small green pair of row rise jeans.
>
> Then you need a validation check; does your SQL have a version of
> grep() or SIMILAR TO predicsates?
>
> CREATE TABLE Inventory
> (sku CHAR(9) NOT NULL PRIMARY KEY
> CHECK (sku SIMILAR TO '[0-9][0-9][0-9]-(grn|blu|wht)-(s|m|l)'),
> ..);
>
> And as you have already noticed, your client is insane not to allow
> all of the attributes in the database in proper columns.
>
>
>>>.. what is a new item comes into stock in a new colour? <<
>
>
> You need to change the validation constraint on the Inventory table to
> allow for a new color code.
Received on Tue Dec 07 2004 - 03:16:05 CET