[ZODB-Dev] Re: [Zope3-dev] Re: Community opinion about search+filter

Jim Fulton jim at zope.com
Sun Mar 25 11:26:00 EDT 2007

On Mar 25, 2007, at 11:08 AM, Lennart Regebro wrote:
>> 2. Use an N-best algorithm.  If N is the size of the batch and M is
>> the corpus size, then this is O(M*ln(N)) rather than O(M*ln(M)) which
>> is a significant improvement if N << M, but still quite expensive.
>> I don't think relational databases have any magic bullet to get
>> around sorting costs.  Sorting is expensive.  In many ways, I think
>> the sorting support in the catalog gave people a false sense of
>> security.
> I don't know if relational databases typically does this internally (I
> don't think so). However, some search engines do it, like Lucene. And
> supposedly also Dieters IncrementalSearch (haven't used it yet).

Our catalog framework also has N-best support.


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