4150 explain implementation checkpoint

1 files changed, 54 insertions, 0 deletions

diff --git a/jstests/explain4.js b/jstests/explain4.js
new file mode 100644
index 00000000000..bc997639ee8
--- /dev/null
+++ b/jstests/explain4.js
@@ -0,0 +1,54 @@
+// Basic validation of explain output fields
+
+t = db.jstests_explain4;
+t.drop();
+
+function checkField( name, value ) {
+    assert( explain.hasOwnProperty( name ) );
+    if ( value != null ) {
+        assert.eq( value, explain[ name ], name );
+    }
+}
+
+function checkPlanFields( explain, matches, n ) {
+    checkField( "cursor", "BasicCursor" );
+    checkField( "n", n );
+    checkField( "nscannedObjects", matches );
+    checkField( "nscanned", matches );    
+    checkField( "indexBounds", {} );
+}
+
+function checkFields( matches, sort, limit ) {
+    it = t.find();
+    if ( sort ) {
+        it.sort({a:1});
+    }
+    if ( limit ) {
+        it.limit( limit );
+    }
+    explain = it.explain( true );
+    printjson( explain );
+    checkPlanFields( explain, matches, matches > 0 ? 1 : 0 );
+    checkField( "scanAndOrder", sort );
+    checkField( "millis" );
+    checkField( "nYields" );
+    checkField( "nChunkSkips", 0 );
+    checkField( "isMultiKey", false );
+//    checkField( "indexOnly", false );
+    checkField( "server" );
+    checkField( "allPlans" );
+    explain.allPlans.forEach( function( x ) { checkPlanFields( x, matches ); } );
+}
+
+checkFields( 0, false );
+checkFields( 0, true );
+
+t.save( {} );
+checkFields( 1, false );
+checkFields( 1, true );
+
+t.save( {} );
+checkFields( 1, false, 1 );
+//checkFields( 2, true, 1 );
+//
+//// check all other fields, eg oldPlan