Jackrabbit Oak - Lucene Index

Refer to OAK-2853 for details. Enabling the Lucene46 codec would lead to smaller and compact indexes.

Boost and Search Relevancy

@since Oak 1.2.5

When fulltext indexing is enabled then internally Oak would create a fulltext field which consists of text extracted from various other fields i.e. fields for which nodeScopeIndex is true. This allows search like //*[jcr:contains(., 'foo')] to perform search across any indexable field containing foo (See contains function for details)

In certain cases its desirable that those nodes where the searched term is present in a specific property are ranked higher (come earlier in search result) compared to those node where the searched term is found in some other property.

In such cases it should be possible to boost specific text contributed by individual property. Meaning that if a title field is boosted more than description, then search result would those node coming earlier where searched term is found in title field

For that to work ensure that for each such property (which need to be preferred) both nodeScopeIndex and analyzed are set to true. In addition you can specify boost property so give higher weightage to values found in specific property

Note that even without setting explicit boost and just setting nodeScopeIndex and analyzed to true would improve the search result due to the way Lucene does scoring. Internally Oak would create separate Lucene fields for those jcr properties and would perform a search across all such fields. For more details refer to OAK-3367

+ +

  + indexRules
+    - jcr:primaryType = "nt:unstructured"
+    + app:Asset
+      + properties
+        - jcr:primaryType = "nt:unstructured"
+        + description
+          - nodeScopeIndex = true
+          - analyzed = true
+          - name = "jcr:content/metadata/jcr:description"
+        + title
+          - analyzed = true
+          - nodeScopeIndex = true
+          - name = "jcr:content/metadata/jcr:title"
+          - boost = 2.0
+

With above index config a search like

+ +

SELECT
+  *
+FROM [app:Asset] 
+WHERE 
+  CONTAINS(., 'Batman')
+

Would have those node (of type app:Asset) come first where Batman is found in jcr:title. While those nodes where search text is found in other field like aggregated content would come later

Boost and Search Relevancy

LuceneIndexProvider Configuration