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?