From 91c4607f7697ee2d5e7c10d65e8ba340aaf5478c Mon Sep 17 00:00:00 2001
From: Aaron <aaron@10gen.com>
Date: Mon, 6 Apr 2009 17:32:40 -0400
Subject: [PATCH] make simple find faster

---
 db/btree.h         | 2 ++
 db/btreecursor.cpp | 8 +++++---
 db/query.cpp       | 7 +++++--
 3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/db/btree.h b/db/btree.h
index 5413b270d78..fddfd3fcee8 100644
--- a/db/btree.h
+++ b/db/btree.h
@@ -274,6 +274,8 @@ namespace mongo {
             return prettyKey( endKey );
         }
         
+        void forgetEndKey() { endKey = BSONObj(); }
+        
     private:
         /* Our btrees may (rarely) have "unused" keys when items are deleted.
            Skip past them.
diff --git a/db/btreecursor.cpp b/db/btreecursor.cpp
index f2bf8546697..7665fb40962 100644
--- a/db/btreecursor.cpp
+++ b/db/btreecursor.cpp
@@ -82,9 +82,11 @@ namespace mongo {
     void BtreeCursor::checkEnd() {
         if ( bucket.isNull() )
             return;
-        int cmp = sgn( endKey.woCompare( currKey(), order ) );
-        if ( cmp != 0 && cmp != direction )
-            bucket = DiskLoc();
+        if ( !endKey.isEmpty() ) {
+            int cmp = sgn( endKey.woCompare( currKey(), order ) );
+            if ( cmp != 0 && cmp != direction )
+                bucket = DiskLoc();
+        }
     }
 
     bool BtreeCursor::advance() {
diff --git a/db/query.cpp b/db/query.cpp
index 5164ba629b7..54b6db7845c 100644
--- a/db/query.cpp
+++ b/db/query.cpp
@@ -857,10 +857,13 @@ namespace mongo {
             query_ = spec_.getObjectField( "query" );
             spec_.getObjectField( "fields" ).getFieldNames( fields_ );
             c_ = qp().newCursor();
-            if ( qp().exactKeyMatch() && fields_.empty() )
+            if ( qp().exactKeyMatch() && fields_.empty() ) {
                 bc_ = dynamic_cast< BtreeCursor* >( c_.get() );
-            else
+                bc_->forgetEndKey();
+            }
+            else {
                 matcher_.reset( new JSMatcher( query_ ) );
+            }
         }
         virtual void next() {
             if ( !c_->ok() ) {