Filter queries are not actually related to ranking, but user requests
have pointed out that specific boost queries to move results to the end
of the result list are not sufficient. Such boost filters may be better
executed as actual filter and therefore such a filter can now be
statically applied to every search request. A typical use could be the
expression "http_unique_b:true AND www_unique_b:true" which uses the
recently introduced fields http_unique_b and www_unique_b which are true
only for one of the alternatives with/without http(s) and with/without
prefix 'www.' in host names.
- an existing ranking servlet for solr was extended. It is now possible
to set boost values for fields, boost functions and boost queries.
- The ranking can have different instances, but currently only the first
one is used
- added an abstraction layer for fields which can be used for search and
those fields can be edited in the solr ranking configruation
- the ranking value from solr within the field score is used to combine
remote search requests, which all are created using the same locally
defined boost values
- reduced the number of fields which are used for search (makes it
faster)
- replaced some text fields by string fields (makes indexing faster)
- removed classes which had no use
- made a large number of experiments for a better ranking and created a
temporary setting which prefers hits inside titles
- adjusted also the RWI-based ranking computation to 'prefer title'
- made special cases like for portal search where no post-processing and
post-ranking is wanted: this keeps the original ranking order as done by
Solr
- fixed many bugs with old settings for ranking
