Subject Re: [Firebird-Architect] Bi-directional indexes
Author Doug Chamberlin
At 6/24/2005 05:38 PM (Friday), Ann W. Harrison wrote:
>Does this make any sense? Does it seem like a good idea?

Here's an idea for Firebird 2: Whenever an index is requested, always
create both an ascending and descending index. Yes, create two separate
indexes automatically, just the way DBA's should if they want the
performance a descending index would yield. That way the current indexing
mechanism would stay intact and only the optimizer needs to be educated
about which to use (which I think it already knows).

Cost: twice the indexing being done.

Benefit: No need to further analyze the indexing mechanism at the moment or
incur risks associated with a change to it. Save this for work farther down
the road to Firebird 3 when an ODS change is already imminent.