Re: Subselects open issue Nr. NEW

From: Zeugswetter Andreas SARZ <Andreas(dot)Zeugswetter(at)telecom(dot)at>
To: "'pgsql-hackers(at)hub(dot)org'" <pgsql-hackers(at)hub(dot)org>
Subject: Re: Subselects open issue Nr. NEW
Date: 1998-02-17 09:34:37
Message-ID: 219F68D65015D011A8E000006F8590C6010A51DC@sdexcsrv1.sd.spardat.at
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Sorry, I take back my gordian knot, I found it in my own brains ;-(
For a <=, <, >=, > a lexical ordering would be more intuitive,
since that is how a compound index would sort.

so (a, b) <= (c, d) would resolve to:
(a <= c) or ((a = c) and (b <= c))

What happens to !=~ ? Should also be _OR_ ed.
I guess that leaves us at a point of no go. Take it out ? *tear drops
falling*

Andreas

> Vectors cannot be strictly ordered. "Partial orderings" are possible.

I think it should say: an order has to be defined (lexical, vector lenght,
area size ..... )

>
> Let A be (1, 2)
> Let B be (4, 7)
> Let C be (3, 5)
> Let D be (5, 10)
>
> A is smallest; D is largest; how do B and C relate?

Browse pgsql-hackers by date

  From Date Subject
Next Message Brandon Ibach 1998-02-17 10:02:05 Re: [HACKERS] Shared tables
Previous Message Zeugswetter Andreas SARZ 1998-02-17 08:52:50 Re: Subselects open issue Nr. NEW