lucene-solr-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Fuad Efendi" <f...@efendi.ca>
Subject RE: SOLR vs SQL
Date Wed, 02 Sep 2009 16:40:48 GMT
> This article explains in-depth why calculating facets is not practical in
> pure SQL: http://www.kimbly.com/blog/000239.html
-> "The problem is that SQL isn't really capable of expressing set
intersections."


But this article is not applicable to described use case: we are
_faceting_on_filtered_query_results_only_, and filters are defined by facets
(same as).

- no need to count docset intersections in this specific use case. Just
execute 20 SQL queries with filters (if you have 20 'foreign keys' for an
entity). Performance is like [log(n)] where n is index size... with SOLR, it
is linear, it is not log(n)...

Same with SOLR vs. Lucene, standard Lucene queries "filter1:value1 AND
facet2:value2" ... "filter1:value1 AND facet2:value99" are functionally the
same as SOLR faceting (99 docset intersections in RAM) and (sooner or later)
implementation and performance will be similar very close (Lucene vs.
SOLR)...




Mime
View raw message