Re: order by, for custom types

Grzegorz Jaskiewicz <gj@pointblue.com.pl> writes:
> Wildcards cause things not to work as they should

> consider everything in [] brackets to be a possible choice and those  
> three:

> a = 1.2.3.4
> b = 1.[2,3].3.4
> c = 1.3.3.4

> a = b, b = c, but a <> c, I was told that because of that btree won't  
> work on my type. (on irc, that was AndrewSN as I recall).

Well, neither will sorting then.  If you can define a consistent sort
order, btree will work; if you can't, then you can't sort either.
AFAICS, with rules like the above you can't define a consistent <
operator.
        regards, tom lane