Apache Solr Reference Guide Covering Apache Solr 6.0

For simple queries, the clustering time will usually dominate the fetch time. If the document content is very long
the retrieval of stored content can become a bottleneck. The performance impact of clustering can be lowered in
several ways:
feed less content to the clustering algorithm by enabling carrot.produceSummary attribute,
perform clustering on selected fields (titles only) to make the input smaller,
use a faster algorithm (STC instead of Lingo, Lingo3G instead of STC),
tune the performance attributes related directly to a specific algorithm.
Some of these techniques are described in Apache SOLR and Carrot2 integration strategies document, available
at http://carrot2.github.io/solr-integration-strategies. The topic of improving performance is also included in the
Carrot2 manual at http://doc.carrot2.org/#section.advanced-topics.fine-tuning.performance.
Additional Resources
The following resources provide additional information about the clustering component in Solr and its potential
applications.
Apache Solr and Carrot2 integration strategies: http://carrot2.github.io/solr-integration-strategies
Apache Solr Wiki (covers previous Solr versions, may be inaccurate): http://carrot2.github.io/solr-integratio
n-strategies
Clustering and Visualization of Solr search results (video from Berlin BuzzWords conference, 2011): http://
vimeo.com/26616444
Spatial Search
Solr supports location data for use in spatial/geospatial searches. Using spatial search, you can:
Index points or other shapes
Filter search results by a bounding box or circle or by other shapes
Sort or boost scoring by distance between points, or relative area between rectangles
Generate a 2D grid of facet count numbers for heatmap generation or point-plotting.
There are three main field types available for spatial search:
LatLonType and its non-geodetic twin PointType
SpatialRecursivePrefixTreeFieldType (RPT for short), including RptWithGeometrySpatialF
ield, a derivative
BBoxField
RPT offers more features than LatLonType and fast filter performance, although LatLonType is more appropriate
when efficient distance sorting/boosting is desired. They can both be used simultaneously for what each does
best – LatLonType for sorting/boosting, RPT for filtering. If you need to index shapes other than points (e.g. a
circle or polygon) then use RPT.
BBoxField is for indexing bounding boxes, querying by a box, specifying a search predicate
(Intersects,Within,Contains,Disjoint,Equals), and a relevancy sort/boost like overlapRatio or simply the area.
Some details that are not in this guide can be found at http://wiki.apache.org/solr/SpatialSearch.
Indexing and Configuration
For indexing geodetic points (latitude and longitude), supply the pair of numbers as a string with a comma
separating them in latitude then longitude order. For non-geodetic points, the order is x,y for PointType, and for
RPT you must use a space instead of a comma, or use WKT.
Apache Solr Reference Guide 6.0
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