On Thu, 2006-02-16 at 21:33 -0800, David Lang wrote:
> > In SQL_ASCII, just take the first 4 characters (or 8, if using a 64-bit
> > sortKey as elsewhere suggested). The sorting key doesn't need to be a
> > one-to-one mapping.
>
> that would violate your second contraint ( f(a)==f(b) iff (a==b) )
could see doing it for char(n)/varchar(n) where n<=4 in SQL_ASCII though.
In SQL_ASCII, just take the first 4 characters (or 8, if using a 64-bit
sortKey as elsewhere suggested). The sorting key doesn't need to be a
one-to-one mapping.
-- Mark Lewis
--
uld always use f(x)=0 as the
default sortKey function which would degenerate to the exact same sort
behavior in use today.
-- Mark Lewis
---(end of broadcast)---
TIP 2: Don't 'kill -9' the postmaster
operations != passes. If you were clever, you could probably write a
modified bubble-sort algorithm that only made 2 passes. A pass is a
disk scan, operations are then performed (hopefully in memory) on what
you read from the disk. So there's no theoretical log N lower-bound on
the number of dis