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Session: Querying: Debugging: How to include Query Explanations

includeExplanations allows to investigate details related to score assigned for each query result.

Syntax

IDocumentQuery<T> includeExplanations(Reference<Explanations> explanations);

Example

Reference<Explanations> explanationRef = new Reference<>();
List<Product> syrups = session.advanced().documentQuery(Product.class)
    .includeExplanations(explanationRef)
    .search("Name", "Syrup")
    .toList();

String[] scoreDetails = explanationRef.value.getExplanations(syrups.get(0).getId());
from Products 
where search(Name, 'Syrup')
include explanations()


Sample explanation:

4.650658 = (MATCH) fieldWeight(search(Name):syrup in 2), product of:
  1 = tf(termFreq(search(Name):syrup)=1)
  4.650658 = idf(docFreq=1, maxDocs=77)
  1 = fieldNorm(field=search(Name), doc=2)