Package org.apache.lucene.search.join
Class ToParentBlockJoinQuery
java.lang.Object
org.apache.lucene.search.Query
org.apache.lucene.search.join.ToParentBlockJoinQuery
This query requires that you index children and parent docs as a single block, using the
IndexWriter.addDocuments()
or IndexWriter.updateDocuments()
API. In each block, the child documents must appear first, ending
with the parent document. At search time you provide a Filter identifying the parents, however
this Filter must provide an BitSet
per sub-reader.
Once the block index is built, use this query to wrap any sub-query matching only child docs and join matches in that child document space up to the parent document space. You can then use this Query as a clause with other queries in the parent document space.
See ToChildBlockJoinQuery
if you need to join in the reverse order.
The child documents must be orthogonal to the parent documents: the wrapped child query must never return a parent document.
See org.apache.lucene.search.join
for an overview.
- WARNING: This API is experimental and might change in incompatible ways in the next release.
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Constructor Summary
ConstructorDescriptionToParentBlockJoinQuery
(Query childQuery, BitSetProducer parentsFilter, ScoreMode scoreMode) Create a ToParentBlockJoinQuery. -
Method Summary
Modifier and TypeMethodDescriptioncreateWeight
(IndexSearcher searcher, ScoreMode weightScoreMode, float boost) boolean
Return our child query.int
hashCode()
rewrite
(IndexReader reader) void
visit
(QueryVisitor visitor) Methods inherited from class org.apache.lucene.search.Query
classHash, sameClassAs, toString
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Constructor Details
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ToParentBlockJoinQuery
Create a ToParentBlockJoinQuery.- Parameters:
childQuery
- Query matching child documents.parentsFilter
- Filter identifying the parent documents.scoreMode
- How to aggregate multiple child scores into a single parent score.
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Method Details
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visit
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createWeight
public Weight createWeight(IndexSearcher searcher, ScoreMode weightScoreMode, float boost) throws IOException - Overrides:
createWeight
in classQuery
- Throws:
IOException
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getChildQuery
Return our child query. -
rewrite
- Overrides:
rewrite
in classQuery
- Throws:
IOException
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toString
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equals
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hashCode
public int hashCode()
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