--- In firebird-support@yahoogroups.com, Helen Borrie <helebor@t...>
wrote:

>
> An index can't be larger than 253 bytes. In many character sets

it is

> less, in some cases a LOT less. Also, multi-segment indexes eat

even more

> out of those 253 bytes.

Yep. For me I am using UNICODE_FSS, so each segment can only be
VARCHAR(84). Sigh. Lots of segments. And I may have misunderstood
the trigger, but I think mine would be just the opposite. I would be
inserting Full_Path, and substringing that out to each segment. Does
that make sense?