From 4d3100a66d881093cb1d7ae1a1af481845585012 Mon Sep 17 00:00:00 2001
From: Aaron <aaron@10gen.com>
Date: Thu, 26 Feb 2009 15:09:44 -0500
Subject: [PATCH] More accurate nScanned recording with plan

---
 db/queryoptimizer.cpp           | 8 +++++++-
 dbtests/queryoptimizertests.cpp | 3 +++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/db/queryoptimizer.cpp b/db/queryoptimizer.cpp
index 451114d2575..d4da09bd532 100644
--- a/db/queryoptimizer.cpp
+++ b/db/queryoptimizer.cpp
@@ -302,19 +302,24 @@ namespace mongo {
         }
         
         int nScanned = 0;
+        int nScannedBackup = 0;
         while( 1 ) {
             ++nScanned;
             unsigned errCount = 0;
+            bool first = true;
             for( vector< shared_ptr< QueryOp > >::iterator i = ops.begin(); i != ops.end(); ++i ) {
                 QueryOp &op = **i;
                 nextOp( op );
                 if ( op.complete() ) {
+                    if ( first )
+                        nScanned += nScannedBackup;
                     if ( plans_.mayRecordPlan_ && op.mayRecordPlan() )
                         op.qp().registerSelf( nScanned );
                     return *i;
                 }
                 if ( op.error() )
                     ++errCount;
+                first = false;
             }
             if ( errCount == ops.size() )
                 break;
@@ -332,7 +337,8 @@ namespace mongo {
                 }                
                 plans_.mayRecordPlan_ = true;
                 plans_.usingPrerecordedPlan_ = false;
-                // TODO Don't write wrong nScanned if we complete on another plan.
+                nScannedBackup = nScanned;
+                nScanned = 0;
             }
         }
         return ops[ 0 ];
diff --git a/dbtests/queryoptimizertests.cpp b/dbtests/queryoptimizertests.cpp
index d811fe59223..c39d322dbd2 100644
--- a/dbtests/queryoptimizertests.cpp
+++ b/dbtests/queryoptimizertests.cpp
@@ -796,6 +796,7 @@ namespace QueryOptimizerTests {
                 ScanOnlyTestOp op;
                 s.runOp( op );
                 ASSERT( fromjson( "{$natural:1}" ).woCompare( indexForPattern( ns(), s.fbs().pattern( BSON( "b" << 1 ) ) ) ) == 0 );
+                ASSERT_EQUALS( 1, nScannedForPattern( ns(), s.fbs().pattern( BSON( "b" << 1 ) ) ) );
                 
                 QueryPlanSet s2( ns(), BSON( "a" << 4 ), BSON( "b" << 1 ) );
                 TestOp op2;
@@ -852,6 +853,7 @@ namespace QueryOptimizerTests {
                 theDataFileMgr.insert( ns(), one );
                 deleteObjects( ns(), BSON( "a" << 1 ), false );
                 ASSERT( BSON( "a" << 1 ).woCompare( indexForPattern( ns(), FieldBoundSet( ns(), BSON( "a" << 1 ) ).pattern() ) ) == 0 );
+                ASSERT_EQUALS( 2, nScannedForPattern( ns(), FieldBoundSet( ns(), BSON( "a" << 1 ) ).pattern() ) );
             }
         };
         
@@ -908,6 +910,7 @@ namespace QueryOptimizerTests {
                 assembleRequest( ns(), QUERY( "b" << 99 << "a" << GTE << 0 ).obj, 2, 0, 0, 0, m2 );
                 runQuery( m2, ss );
                 ASSERT( BSON( "a" << 1 ).woCompare( indexForPattern( ns(), FieldBoundSet( ns(), BSON( "b" << 0 << "a" << GTE << 0 ) ).pattern() ) ) == 0 );                
+                ASSERT_EQUALS( 2, nScannedForPattern( ns(), FieldBoundSet( ns(), BSON( "b" << 0 << "a" << GTE << 0 ) ).pattern() ) );
             }
         };