Package org.apache.lucene.search

Class KnnVectorQuery

  • @Deprecated
public class KnnVectorQuery
extends KnnFloatVectorQuery
    Deprecated.
    use KnnFloatVectorQuery instead
    Uses KnnVectorsReader.search(String, float[], int, Bits, int) to perform nearest neighbour search.

    This query also allows for performing a kNN search subject to a filter. In this case, it first executes the filter for each leaf, then chooses a strategy dynamically:

    • If the filter cost is less than k, just execute an exact search
    • Otherwise run a kNN search subject to the filter
    • If the kNN search visits too many vectors without completing, stop and run an exact search

    • Field Detail

      • field

        protected final String field

      • k

        protected final int k

    • Constructor Detail

      • KnnVectorQuery

        public KnnVectorQuery​(String field,
                      float[] target,
                      int k)
        Deprecated.

      • KnnVectorQuery

        public KnnVectorQuery​(String field,
                      float[] target,
                      int k,
                      Query filter)
        Deprecated.

    • Method Detail

      • rewrite

        public Query rewrite​(IndexReader reader)
              throws IOException
        Description copied from class: Query
        Expert: called to re-write queries into primitive queries. For example, a PrefixQuery will be rewritten into a BooleanQuery that consists of TermQuerys.

        Callers are expected to call rewrite multiple times if necessary, until the rewritten query is the same as the original query.

        Overrides:
        rewrite in class Query
        Throws:
        IOException
        See Also:
        IndexSearcher.rewrite(Query)

      • visit

        public void visit​(QueryVisitor visitor)
        Description copied from class: Query
        Recurse through the query tree, visiting any child queries
        Specified by:
        visit in class Query
        Parameters:
        visitor - a QueryVisitor to be called by each query in the tree

      • getField

        public String getField()
        Returns:
        the knn vector field where the knn vector search happens.

      • getK

        public int getK()
        Returns:
        the max number of results the KnnVector search returns.

      • getFilter

        public Query getFilter()
        Returns:
        the filter that is executed before the KnnVector search happens. Only the results accepted by this filter are returned by the KnnVector search.