From a4e4235d93a12cebe397f5225ebc2de1a174dda8 Mon Sep 17 00:00:00 2001
From: Shay Banon <kimchy@gmail.com>
Date: Sat, 31 Dec 2011 16:24:27 +0200
Subject: [PATCH] move sort optimization when sorting by _score to sort parse
 element from the query phase execution

---
 .../elasticsearch/search/query/QueryPhase.java   | 16 +---------------
 .../search/sort/SortParseElement.java            | 16 +++++++++++++++-
 2 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/main/java/org/elasticsearch/search/query/QueryPhase.java b/src/main/java/org/elasticsearch/search/query/QueryPhase.java
index 21dffcb6001..a305d73f2e2 100644
--- a/src/main/java/org/elasticsearch/search/query/QueryPhase.java
+++ b/src/main/java/org/elasticsearch/search/query/QueryPhase.java
@@ -176,20 +176,6 @@ public class QueryPhase implements SearchPhase {
                 // if 0 was asked, change it to 1 since 0 is not allowed
                 numDocs = 1;
             }
-            boolean sort = false;
-            // try and optimize for a case where the sorting is based on score, this is how we work by default!
-            if (searchContext.sort() != null) {
-                if (searchContext.sort().getSort().length > 1) {
-                    sort = true;
-                } else {
-                    SortField sortField = searchContext.sort().getSort()[0];
-                    if (sortField.getType() == SortField.SCORE && !sortField.getReverse()) {
-                        sort = false;
-                    } else {
-                        sort = true;
-                    }
-                }
-            }
 
             if (searchContext.searchType() == SearchType.COUNT) {
                 CountCollector countCollector = new CountCollector();
@@ -207,7 +193,7 @@ public class QueryPhase implements SearchPhase {
                     // all is well
                 }
                 topDocs = scanCollector.topDocs();
-            } else if (sort) {
+            } else if (searchContext.sort() != null) {
                 topDocs = searchContext.searcher().search(query, null, numDocs, searchContext.sort());
             } else {
                 topDocs = searchContext.searcher().search(query, numDocs);
diff --git a/src/main/java/org/elasticsearch/search/sort/SortParseElement.java b/src/main/java/org/elasticsearch/search/sort/SortParseElement.java
index bbf2a51b9df..eb72e40c023 100644
--- a/src/main/java/org/elasticsearch/search/sort/SortParseElement.java
+++ b/src/main/java/org/elasticsearch/search/sort/SortParseElement.java
@@ -76,7 +76,21 @@ public class SortParseElement implements SearchParseElement {
             addCompoundSortField(parser, context, sortFields);
         }
         if (!sortFields.isEmpty()) {
-            context.sort(new Sort(sortFields.toArray(new SortField[sortFields.size()])));
+            // optimize if we just sort on score non reversed, we don't really need sorting
+            boolean sort;
+            if (sortFields.size() > 1) {
+                sort = true;
+            } else {
+                SortField sortField = sortFields.get(0);
+                if (sortField.getType() == SortField.SCORE && !sortField.getReverse()) {
+                    sort = false;
+                } else {
+                    sort = true;
+                }
+            }
+            if (sort) {
+                context.sort(new Sort(sortFields.toArray(new SortField[sortFields.size()])));
+            }
         }
     }