Offset that the search results are matched afterįragment of a hit result’s content where the query term(s) matchĮxplanation of how the hit result’s score is calculated Threshold to include results with scores above or equal Results received from the search index for a queryĬalculated score between a query and a hit result With the SERVICE clause syntax, we specify each parameter by name listed in the table below: Not only does it make the arguments clear, but also provides some additional features, such as the ability of searching over variable bindings, returning highlighted fragments or getting explanations of search result scores. An alternate syntax based on SPARQL SERVICE clause is provided. With up to four input constants and two or more output variables, positional arguments can become confusing. The textMatch predicate is concise for simple queries. Note that, as explained in the Lucene documentation scoring is very much dependent on the way documents are indexed and the range of scores might change significantly between different databases. This query returns 10 matching literals where the score is greater than 0.5. It is possible to return these scores and define filters based on the score: SELECT DISTINCT ?s ?score When a LIMIT is specified in the SPARQL query, it does not affect the full-text search, rather, it only restricts the size of the result set. Limit in textMatch only limits the number of literals returned, which is different than the number of total results the query will return. You can change the number of results textMatch returns by providing an optional second argument with the limit: SELECT DISTINCT ?s ?score Alternatively, you could use ?s rdf:type ex:Book if you only wanted to select the books which reference the search criteria you can include as many other BGPs as you like to enhance your initial search results. These literals are then joined with the generic BGP ?s ?p ?l to get the resources ( ?s) that have those literals. This query selects all literals which match ‘mac’. The textMatch function has one required argument, the search query in Lucene Syntax and it returns, by default, all literals matching the query string. We use the predicate tag:stardog:api:property:textMatch (or ) to access the search index in a SPARQL query. Similarly, you can set the option using SearchOptions.SEARCHABLE when creating the database programmatically: // Create a database with full-text index For example, you can create a database with full-text support as follows:įrom CLI $ stardog-admin db create -o search.enabled=true -n myDb Enabling Searchįull-text support for a database is disabled by default but can be enabled at any time by setting the configuration option search.enabled to true. See Custom Analyzer for details on customizing Stardog’s search programmatically. Each document consists of two fields: literal ID and literal value. The indexing strategy creates a “search document” per RDF literal. Search is not supported over data in virtual sources. Stardog’s built-in full-text search system indexes data stored in Stardog for information retrieval queries. Escaping Characters over Variable Bindings.Applying Customization to Existing Databases.Inclusion or Exclusion List of Contexts.Getting Explanation of Search Result Scores. This page discusses Stardog’s full-text search capabilities.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |