SERVER-10026 enumeration as strategies, bug fixes galore, build plans

1 files changed, 14 insertions, 0 deletions

diff --git a/src/mongo/db/query/index_tag.h b/src/mongo/db/query/index_tag.h
index ee8791c38ba..51178af9149 100644
--- a/src/mongo/db/query/index_tag.h
+++ b/src/mongo/db/query/index_tag.h
@@ -24,7 +24,9 @@ namespace mongo {
     // XXX
     class IndexTag : public MatchExpression::TagData {
     public:
+        static const size_t kNoIndex;
 
+        IndexTag() : index(kNoIndex) {}
         IndexTag(size_t i) : index(i) { }
 
         virtual ~IndexTag() { }
@@ -41,4 +43,16 @@ namespace mongo {
         size_t index;
     };
 
+    /**
+     * Tags each node of the tree with the lowest numbered indexed that the sub-tree
+     * rooted at that node uses.
+     */
+    void tagForSort(MatchExpression* tree);
+
+    /**
+     * Then sorts the tree using its IndexTag()s. The outcome is that nodes that use the same index
+     * are adjacent to one another.
+     */
+    void sortUsingTags(MatchExpression* tree);
+
 } // namespace mongo