--- In firebird-support@yahoogroups.com, David Johnson wrote:

>> The article did not make it clear to me why a SELECT MAX() could
>> not profit from an ascending index.
>
> An ascending index would have to be traversed backwards to get a true
> max. Firebird opted for unidirectional indexes (like DB2, which is a
> locking database).

Please bear with me, I still fail to grasp it.
Why is it so much more expensive to get that last entry (or last
couple of entries) from a B*-Tree than it is to get the first entry?

Laurenz Albe