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Date: Tue, 24 Apr 2007 13:40:52 +0100
From: Richard Huxton <dev@archonet.com>
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To: Dmitry Turin <sql4-en@narod.ru>
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Subject: Re: Fwd: Re[2]: We all are looped on Internet: request + transport
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Dmitry Turin wrote:
> Good day, Joe.
> 
>>>> I would change your examples to use less abstract
>>>> data, like department/employee, customer/product/order/order_line
> 
> J> I contend that then you'd find more people
> J> receptive to your ideas or at least able to criticize them from more
> J> concrete viewpoints.
> 
> I expected, that you already read
> http://sql4.by.ru/site/sql40/en/author/wave_eng.htm
> (i added output into this paper).
> Case of "department/employee" is "Example 1" on this paper.

I'd not expect people to read lengthy articles on a general-questions 
mailing list, but I've skimmed at least as far as example 2.

1. What does it mean for one flight to be contained within another? I 
can see how one flight might follow another, but not contained. Do you 
not need some new object "flight_chain" or similar?

2. Surely a flight should contain two cities (since it connects two 
cities). Alternatively, the <city> needs to indicate to which it's 
referring either as <startcity>/<endcity> or <city fromto="start"> or 
similar.

3. How am I constructing these queries? The whole point was so I didn't 
have to learn SQL, yes? Unfortunately, the syntax for these queries 
isn't obvious enough to me that I can see how to write them without some 
form of query-builder, or reference manual.

4. How am I using these queries? I'm still not clear what use it is to 
have XML without a schema. Let's say I want to build a holiday website. 
How does this TML setup avoid me having to write any php/perl/etc?

-- 
   Richard Huxton
   Archonet Ltd