Re: [SQL] index row size 2728 exceeds btree maximum, 27

On Thu, Jun 02, 2005 at 13:40:53 +0100,
  Richard Huxton <dev@archonet.com> wrote:
>
> Actually, Dinesh didn't mention he was using this for the speed of
> lookup. He'd defined the columns as being the PRIMARY KEY, presumably
> because he feels they are/should be unique. Given that they are rows
> from a logfile, I'm not convinced this is the case.

Even for case you could still use hashes. The odds of a false collision
using SHA-1 are so small that some sort of disaster is more likely.
Another possibility is if there are a fixed number of possible messages,
is that they could be entered in their own table with a serail PK and
the other table could reference the PK.