An implementation of index intersect via a modified Unique class.

This code is planned to be used for mwl#21.

1 files changed, 55 insertions, 6 deletions

diff --git a/sql/opt_range.h b/sql/opt_range.h
index f2a1cce29b5..0be082e4c9a 100644
--- a/sql/opt_range.h
+++ b/sql/opt_range.h
@@ -274,12 +274,13 @@ public:
 
   enum {
     QS_TYPE_RANGE = 0,
-    QS_TYPE_INDEX_MERGE = 1,
-    QS_TYPE_RANGE_DESC = 2,
-    QS_TYPE_FULLTEXT   = 3,
-    QS_TYPE_ROR_INTERSECT = 4,
-    QS_TYPE_ROR_UNION = 5,
-    QS_TYPE_GROUP_MIN_MAX = 6
+    QS_TYPE_INDEX_INTERSECT = 1,
+    QS_TYPE_INDEX_MERGE = 2,
+    QS_TYPE_RANGE_DESC = 3,
+    QS_TYPE_FULLTEXT   = 4,
+    QS_TYPE_ROR_INTERSECT = 5,
+    QS_TYPE_ROR_UNION = 6,
+    QS_TYPE_GROUP_MIN_MAX = 7
   };
 
   /* Get type of this quick select - one of the QS_TYPE_* values */
@@ -393,8 +394,17 @@ protected:
   friend QUICK_RANGE_SELECT *get_quick_select(PARAM*,uint idx,
                                               SEL_ARG *key_tree,
                                               MEM_ROOT *alloc);
+  friend 
+  int read_keys_and_merge_scans(THD *thd, TABLE *head,
+                                List<QUICK_RANGE_SELECT> quick_selects,
+                                QUICK_RANGE_SELECT *pk_quick_select,
+                                READ_RECORD *read_record,
+                                bool intersection,
+                                Unique **unique_ptr);
+
   friend class QUICK_SELECT_DESC;
   friend class QUICK_INDEX_MERGE_SELECT;
+  friend class QUICK_INDEX_INTERSECT_SELECT;
   friend class QUICK_ROR_INTERSECT_SELECT;
   friend class QUICK_GROUP_MIN_MAX_SELECT;
 
@@ -545,6 +555,45 @@ public:
   READ_RECORD read_record;
 };
 
+class QUICK_INDEX_INTERSECT_SELECT : public QUICK_SELECT_I
+{
+  Unique *unique;
+public:
+  QUICK_INDEX_INTERSECT_SELECT(THD *thd, TABLE *table);
+  ~QUICK_INDEX_INTERSECT_SELECT();
+
+  int  init();
+  int  reset(void);
+  int  get_next();
+  bool reverse_sorted() { return false; }
+  bool unique_key_range() { return false; }
+  int get_type() { return QS_TYPE_INDEX_INTERSECT; }
+  void add_keys_and_lengths(String *key_names, String *used_lengths);
+  void add_info_string(String *str);
+  bool is_keys_used(const MY_BITMAP *fields);
+#ifndef DBUG_OFF
+  void dbug_dump(int indent, bool verbose);
+#endif
+
+  bool push_quick_back(QUICK_RANGE_SELECT *quick_sel_range);
+
+  /* range quick selects this index_merge read consists of */
+  List<QUICK_RANGE_SELECT> quick_selects;
+
+  /* quick select that uses clustered primary key (NULL if none) */
+  QUICK_RANGE_SELECT* pk_quick_select;
+
+  /* true if this select is currently doing a clustered PK scan */
+  bool  doing_pk_scan;
+
+  MEM_ROOT alloc;
+  THD *thd;
+  int read_keys_and_merge();
+
+  /* used to get rows collected in Unique */
+  READ_RECORD read_record;
+};
+
 
 /*
   Rowid-Ordered Retrieval (ROR) index intersection quick select.