|
|
@@ -37,6 +37,18 @@ be used for highlighting if it mapped to have `store` set to `true`.
|
|
|
The field name supports wildcard notation. For example, using `comment_*`
|
|
|
will cause all fields that match the expression to be highlighted.
|
|
|
|
|
|
+[[plain-highlighter]]
|
|
|
+==== Plain highlighter
|
|
|
+
|
|
|
+The default choice of highlighter is of type `plain` and uses the Lucene highlighter.
|
|
|
+It tries hard to reflect the query matching logic in terms of understanding word importance and any word positioning criteria in phrase queries.
|
|
|
+
|
|
|
+[WARNING]
|
|
|
+If you want to highlight a lot of fields in a lot of documents with complex queries this highlighter will not be fast.
|
|
|
+In its efforts to accurately reflect query logic it creates a tiny in-memory index and re-runs the original query criteria through
|
|
|
+Lucene's query execution planner to get access to low-level match information on the current document.
|
|
|
+This is repeated for every field and every document that needs highlighting. If this presents a performance issue in your system consider using an alternative highlighter.
|
|
|
+
|
|
|
[[postings-highlighter]]
|
|
|
==== Postings highlighter
|
|
|
|
markharwood