Manual merge.

3 files changed, 45 insertions, 7 deletions

diff --git a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc
index 5415d6f4f8a..26be4018de8 100644
--- a/sql/item_cmpfunc.cc
+++ b/sql/item_cmpfunc.cc
@@ -5292,7 +5292,8 @@ Item *Item_bool_rowready_func2::negated_item()
 }
 
 Item_equal::Item_equal(Item_field *f1, Item_field *f2)
-  : Item_bool_func(), const_item(0), eval_item(0), cond_false(0)
+  : Item_bool_func(), const_item(0), eval_item(0), cond_false(0),
+    compare_as_dates(FALSE)
 {
   const_item_cache= 0;
   fields.push_back(f1);
@@ -5305,6 +5306,7 @@ Item_equal::Item_equal(Item *c, Item_field *f)
   const_item_cache= 0;
   fields.push_back(f);
   const_item= c;
+  compare_as_dates= f->is_datetime();
 }
 
 
@@ -5319,9 +5321,45 @@ Item_equal::Item_equal(Item_equal *item_equal)
     fields.push_back(item);
   }
   const_item= item_equal->const_item;
+  compare_as_dates= item_equal->compare_as_dates;
   cond_false= item_equal->cond_false;
 }
 
+
+void Item_equal::compare_const(Item *c)
+{
+  if (compare_as_dates)
+  {
+    cmp.set_datetime_cmp_func(this, &c, &const_item);
+    cond_false= cmp.compare();
+  }
+  else
+  {
+    Item_func_eq *func= new Item_func_eq(c, const_item);
+    func->set_cmp_func();
+    func->quick_fix_field();
+    cond_false= !func->val_int();
+  }
+  if (cond_false)
+    const_item_cache= 1;
+}
+
+
+void Item_equal::add(Item *c, Item_field *f)
+{
+  if (cond_false)
+    return;
+  if (!const_item)
+  {
+    DBUG_ASSERT(f);
+    const_item= c;
+    compare_as_dates= f->is_datetime();
+    return;
+  }
+  compare_const(c);
+}
+
+
 void Item_equal::add(Item *c)
 {
   if (cond_false)
@@ -5331,11 +5369,7 @@ void Item_equal::add(Item *c)
     const_item= c;
     return;
   }
-  Item_func_eq *func= new Item_func_eq(c, const_item);
-  func->set_cmp_func();
-  func->quick_fix_field();
-  if ((cond_false= !func->val_int()))
-    const_item_cache= 1;
+  compare_const(c);
 }
 
 void Item_equal::add(Item_field *f)
diff --git a/sql/item_cmpfunc.h b/sql/item_cmpfunc.h
index 52af6a31c0c..e2c070e2bdb 100644
--- a/sql/item_cmpfunc.h
+++ b/sql/item_cmpfunc.h
@@ -1583,7 +1583,9 @@ class Item_equal: public Item_bool_func
   List<Item_field> fields; /* list of equal field items                    */
   Item *const_item;        /* optional constant item equal to fields items */
   cmp_item *eval_item;
+  Arg_comparator cmp;
   bool cond_false;
+  bool compare_as_dates;
 public:
   inline Item_equal()
     : Item_bool_func(), const_item(0), eval_item(0), cond_false(0)
@@ -1592,6 +1594,8 @@ public:
   Item_equal(Item *c, Item_field *f);
   Item_equal(Item_equal *item_equal);
   inline Item* get_const() { return const_item; }
+  void compare_const(Item *c);
+  void add(Item *c, Item_field *f);
   void add(Item *c);
   void add(Item_field *f);
   uint members();
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index b2a4958020a..8a5a8176561 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -7527,7 +7527,7 @@ static bool check_simple_equality(Item *left_item, Item *right_item,
           already contains a constant and its value is  not equal to
           the value of const_item.
         */
-        item_equal->add(const_item);
+        item_equal->add(const_item, field_item);
       }
       else
       {