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Robert Tseng commented on SOLR-2155: ------------------------------------ Hi All, New to Solr here! I have a question for you all on gh_geofilt. My document has rows of path, think of KML lineString, of which I want to do bounding box check which of them fall within a box. Each row basically has an id field and a multivalued field describing the line with multiple points. What I want returned is all lines that fall within but I read Solr is not very good, yet, in returning large number of hits. Hence the row params to limit result to top N rows. My two questions are: 1. If want to retrieve all rows, do I query twice from solrj. Once to get number of hits so I can set the number of rows that grabs all row in a second call? Or two I should chunk up the query call using the start params as an offset? 2. If it's only returning top N, is it based on score? What is considered high score? A row with most number of hits in the box? Cloest to the center? > Geospatial search using geohash prefixes > ---------------------------------------- > > Key: SOLR-2155 > URL: https://issues.apache.org/jira/browse/SOLR-2155 > Project: Solr > Issue Type: Improvement > Reporter: David Smiley > Assignee: David Smiley > Attachments: GeoHashPrefixFilter.patch, GeoHashPrefixFilter.patch, > GeoHashPrefixFilter.patch, Solr2155-1.0.2-project.zip, > Solr2155-1.0.3-project.zip, Solr2155-1.0.4-project.zip, > Solr2155-for-1.0.2-3.x-port.patch, > SOLR-2155_GeoHashPrefixFilter_with_sorting_no_poly.patch, SOLR.2155.p3.patch, > SOLR.2155.p3tests.patch > > > {panel:title=NOTICE} The status of this issue is a plugin for Solr 3.x > located here: https://github.com/dsmiley/SOLR-2155. Look at the introductory > readme and download the plugin .jar file. Lucene 4's new spatial module is > largely based on this code. The Solr 4 glue for it should come very soon but > as of this writing it's hosted temporarily at https://github.com/spatial4j. > For more information on using SOLR-2155 with Solr 3, see > http://wiki.apache.org/solr/SpatialSearch#SOLR-2155 This JIRA issue is > closed because it won't be committed in its current form. > {panel} > There currently isn't a solution in Solr for doing geospatial filtering on > documents that have a variable number of points. This scenario occurs when > there is location extraction (i.e. via a "gazateer") occurring on free text. > None, one, or many geospatial locations might be extracted from any given > document and users want to limit their search results to those occurring in a > user-specified area. > I've implemented this by furthering the GeoHash based work in Lucene/Solr > with a geohash prefix based filter. A geohash refers to a lat-lon box on the > earth. Each successive character added further subdivides the box into a 4x8 > (or 8x4 depending on the even/odd length of the geohash) grid. The first > step in this scheme is figuring out which geohash grid squares cover the > user's search query. I've added various extra methods to GeoHashUtils (and > added tests) to assist in this purpose. The next step is an actual Lucene > Filter, GeoHashPrefixFilter, that uses these geohash prefixes in > TermsEnum.seek() to skip to relevant grid squares in the index. Once a > matching geohash grid is found, the points therein are compared against the > user's query to see if it matches. I created an abstraction GeoShape > extended by subclasses named PointDistance... and CartesianBox.... to support > different queried shapes so that the filter need not care about these details. > This work was presented at LuceneRevolution in Boston on October 8th. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org