Re: Fwd: Re[2]: We all are looped on Internet: request + transport = invariant - Mailing list pgsql-sql

Dmitry Turin wrote:
> Good day, Richard.
> 
>>> RH> <flight_chain ...>
>>> RH>    <flight_options>
>>> RH>      <flight...>
>>> RH>      <flight...>  These three flights represent options
>>> RH>      <flight...>
>>> RH>    </flight_options>
>>> RH> </flight_chain>
> RH> 1. A journey (flight_chain) between city A and city Z consists of one or
> RH> more flights.
> RH> 2. The next flight has to start at the current city, but there may be
> RH> several flights to choose from.
> RH> 3. The last flight must end at city Z.
> RH> Now stage 2 groups the flights to choose among - you can call it
> RH> something else, but the equivalent of flight_options is there.
> 
> Tag "city" executed the same role in my version,
> that tag "flight_chain" in your version.

No, it didn't.

>>> RH> 2. If you nest flights then you'll be forced to repeat data, surely?
>>> RH> Multiple routes could end up mentioning flight id=123 several times and
>>> RH> each time have to repeat all possible options from it.
>>>
>>> Yes.
>>> Remember, this is not manner of storing data in DBMS.
>>> This is manner to visualize for man.
> RH> So how do I know it's repeated without grabbing a pencil and paper and
> RH> scrolling back and fore to compare them?
> 
> Write XML-form, which illustrate, what are you want.
> I will write request.

What's that got to do with knowing whether a particular tag is repeated 
elsewhere in a long list.

> RH> Are you sure this wouldn't just be easier if you wrote a specialised
> RH> data-visualiser application?
> 
> Avarage used can not use library of intermediate language
> to join DBMS and browser.

No, I said write your own "TML browser".

> P.S.
> Programmers are small percent of all users.
> 
>>> RH> If I'm going to learn only one query language, it'll be SQL
>>> RH> because everything uses it.
>>>
>>> 'tablename >>;' is better, than to learn php, perl, its library
> RH> But you're not doing the same thing.
> 
> I'm not doing? I have write example!

No, you've provided a way of reformatting query results as XML. That's 
not the same as a public-facing website at all. You don't think British 
Airways will have people querying their database by entering TML queries?

>>> Term "scheme" means "database scheme" to me :)
> RH> But you were talking about XML at the time.
> 
> XML is not stored thing, it is a transport form for scheme.
> Let's ask concrete questions, ok?
> 
>>> RH> I'm sat here at my laptop, and I want to get a
>>> RH> list of flights into a spreadsheet I'm doing for my boss.
>>>
>>> Your boss will itself solve "task of travelling-salesman" ?
>>> By eyes ?
> RH> No, but my boss wants a list of flights from London to Madrid for next
> RH> Friday, with prices, times etc.
> 
> Direct flight?
>  #city[name="London"].flight/c1:c2[#c1 #c2 #day="friday"].#city[name="Madrid"] >>;
> 
> Roundabout flight?
> #city[name="London"].(flight/c1:c2[#day="friday" t1-^^.t2>30min].city)*||name="Madrid" ;
> 
> Prices and times is attributes of FLIGHT.
> These are in Example 2.
> http://sql4.by.ru/site/sql40/en/author/wave_eng.htm
> 
> RH> So what does it matter to me as a user
> 
> User only use.
> Difference between realizations of site is important only for authors
> of site.

So who it *is* the programmer who is using TML then?

> RH>  whether the site is written in TML+Java
> 
> What will Java do ?

As I said in my previous post, everything else (see next two lines 
you've quoted).

> RH> And if I'm building the site in PHP anyway (and I'm going to need
> RH> forms/buttons/etc in some language) then what am I gaining from the TML?
> 
>>> create view x as
>>> select city.name as start, city.name as end, flight.t1, flight.t2, day
>>> from city, flight;
>>> x >>;
> RH> Hang on - you're using SQL. Why not just use pgadmin and paste the
> RH> results from my query if I'm using SQL anyway?
> 
> paste by hands?
> 
> RH> Sorry - you didn't eliminate any code there.
> 
> I simplify code.

Can't see it myself.

> Compare call of php library for database, getting record set,
> embrace records in circle by html-tags, call php library for
> http-communication.

I still don't see the sense in what you're saying. My process is:
1. User goes to website
2. User fills in PHP form: start city, end city, date he wants to fly.
3. PHP generates SQL query and submits to database
4. Database runs query result as table
5. PHP formats results as nicely formatted table with company logos etc.
6. User views results.

Yours is:
1. User goes to website
2. User fills in PHP form: start city, end city, date he wants to fly.
3. PHP generates TML query and submits to database
4. Database runs query result as XML
5. PHP formats results as nicely formatted table with company logos etc.
6. User views results.

What is saved?
And let's not say the user is viewing the raw XML because that's clearly 
no use in a public-facing site.

> RH> But the transport of the data is trivial, assuming I have a webserver
> RH> and PHP/Perl/ASP/etc. available.
> 
> 1. Speak not about you, but about average user.

But you just said the average user isn't building the application/website.

>  You don't know real statistics.
> 2. Even you make superfluous job.

Sounds to me like you want to either build your own browser, or just 
write a server-side application that receives TML and outputs XML. If 
you're serious about this, I recommend looking around for a 
PHP/Perl/Java programmer and hiring them for a week - that should be 
more than enough.

Then, when you've got a few thousand users it will become clearer whats 
actually required.

--   Richard Huxton  Archonet Ltd