1 files changed, 19 insertions, 0 deletions
diff --git a/jstests/querySystemMigration/queryoptimizerb.js b/jstests/querySystemMigration/queryoptimizerb.js
new file mode 100644
index 00000000000..ffcb5614dc1
--- /dev/null
+++ b/jstests/querySystemMigration/queryoptimizerb.js
@@ -0,0 +1,19 @@
+// The query optimizer will not generate 'special' plans inside $or clauses.  SERVER-5936
+
+t = db.jstests_queryoptimizerb;
+t.drop();
+
+t.ensureIndex( { a:'2d' } );
+// Add an index to make the { b:1 } query mongo::HELPFUL but QueryPlan::Unhelpful.
+t.ensureIndex( { c:1, b:1 } );
+
+// A 'special' index is not used for an $or equality match query.
+t.save( { a:[ 0, 0 ], b:1 } );
+assert.eq( 1, t.find( { a:[ 0, 0 ], $or:[ { b:1 } ] } ).itcount() );
+assert.eq( 'BasicCursor', t.find( { a:[ 0, 0 ], $or:[ { b:1 } ] } ).explain().cursor );
+
+// A 'special' index cannot be hinted for a $or query.
+assert.throws( function() {
+               t.find( { a:[ 0, 0 ], $or:[ { a:[ 0, 0 ] } ] } ).hint( { a:'2d' } ).itcount(); } );
+assert.throws( function() {
+               t.find( { a:[ 0, 0 ], $or:[ { a:[ 0, 0 ] } ] } ).hint( { a:'2d' } ).explain(); } );