SERVER-14706 SERVER-14706 negated $type predicates should not use an index

(cherry picked from commit 6bfddeb720b51b88533c7ae453dc5c702fdc58a5)

2 files changed, 11 insertions, 1 deletions

diff --git a/src/mongo/db/query/planner_ixselect.cpp b/src/mongo/db/query/planner_ixselect.cpp
index 2a64df91ae8..bb23e7c2f3d 100644
--- a/src/mongo/db/query/planner_ixselect.cpp
+++ b/src/mongo/db/query/planner_ixselect.cpp
@@ -174,10 +174,11 @@ namespace mongo {
                     return false;
                 }
 
-                // Can't index negations of MOD, REGEX, or ELEM_MATCH_VALUE.
+                // Can't index negations of MOD, REGEX, TYPE_OPERATOR, or ELEM_MATCH_VALUE.
                 MatchExpression::MatchType childtype = node->getChild(0)->matchType();
                 if (MatchExpression::REGEX == childtype ||
                     MatchExpression::MOD == childtype ||
+                    MatchExpression::TYPE_OPERATOR == childtype ||
                     MatchExpression::ELEM_MATCH_VALUE == childtype) {
                     return false;
                 }
diff --git a/src/mongo/db/query/query_planner_test.cpp b/src/mongo/db/query/query_planner_test.cpp
index 5b8eeef200f..b23da60bc05 100644
--- a/src/mongo/db/query/query_planner_test.cpp
+++ b/src/mongo/db/query/query_planner_test.cpp
@@ -2893,6 +2893,15 @@ namespace {
         assertSolutionExists("{cscan: {dir: 1}}");
     }
 
+    // Negated $type doesn't use the index
+    TEST_F(QueryPlannerTest, NegationTypeOperator) {
+        addIndex(BSON("i" << 1));
+        runQuery(fromjson("{i: {$not: {$type: 16}}}"));
+
+        assertNumSolutions(1U);
+        assertSolutionExists("{cscan: {dir: 1}}");
+    }
+
     // Negated $elemMatch value won't use the index
     TEST_F(QueryPlannerTest, NegationElemMatchValue) {
         addIndex(BSON("i" << 1));