[Backport 2.x] Optimize UnsignedLong range queries to convert to MatchNoDocsQuery when lower > upper bounds

CHANGELOG.md

@@ -22,6 +22,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Bump `opentelemetry` from 1.36.0 to 1.39.0 ([#14457](https://github.com/opensearch-project/OpenSearch/pull/14457))
 
 ### Changed
+- unsignedLongRangeQuery now returns MatchNoDocsQuery if the lower bounds are greater than the upper bounds ([#14416](https://github.com/opensearch-project/OpenSearch/pull/14416))
 - Make the class CommunityIdProcessor final ([#14448](https://github.com/opensearch-project/OpenSearch/pull/14448))
 - Updated the `indices.query.bool.max_clause_count` setting from being static to dynamically updateable ([#13568](https://github.com/opensearch-project/OpenSearch/pull/13568))
 

server/src/main/java/org/opensearch/index/mapper/NumberFieldMapper.java

@@ -1410,6 +1410,9 @@ public static Query unsignedLongRangeQuery(
                     u = u.subtract(BigInteger.ONE);
                 }
             }
+            if (l.compareTo(u) > 0) {
+                return new MatchNoDocsQuery();
+            }
             return builder.apply(l, u);
         }
     }

server/src/test/java/org/opensearch/index/mapper/NumberFieldTypeTests.java

@@ -86,6 +86,7 @@
 import java.util.function.Supplier;
 
 import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.either;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.instanceOf;
 
@@ -673,9 +674,11 @@ public void doTestDocValueRangeQueries(NumberType type, Supplier<Number> valueSu
                 true,
                 MOCK_QSC
             );
-            assertThat(query, instanceOf(IndexOrDocValuesQuery.class));
-            IndexOrDocValuesQuery indexOrDvQuery = (IndexOrDocValuesQuery) query;
-            assertEquals(searcher.count(indexOrDvQuery.getIndexQuery()), searcher.count(indexOrDvQuery.getRandomAccessQuery()));
+            assertThat(query, either(instanceOf(IndexOrDocValuesQuery.class)).or(instanceOf(MatchNoDocsQuery.class)));
+            if (query instanceof IndexOrDocValuesQuery) {
+                IndexOrDocValuesQuery indexOrDvQuery = (IndexOrDocValuesQuery) query;
+                assertEquals(searcher.count(indexOrDvQuery.getIndexQuery()), searcher.count(indexOrDvQuery.getRandomAccessQuery()));
+            }
         }
         reader.close();
         dir.close();