5.5 merge

1 files changed, 47 insertions, 24 deletions

diff --git a/sql/item_sum.cc b/sql/item_sum.cc
index e539d0b76b4..c824cc70617 100644
--- a/sql/item_sum.cc
+++ b/sql/item_sum.cc
@@ -1,5 +1,5 @@
 /* Copyright (c) 2000, 2013, Oracle and/or its affiliates.
-   Copyright (c) 2008, 2013 Monty Program Ab
+   Copyright (c) 2008, 2014, SkySQL Ab.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -261,7 +261,7 @@ bool Item_sum::check_sum_func(THD *thd, Item **ref)
     List_iterator<Item_field> of(outer_fields);
     while ((field= of++))
     {
-      SELECT_LEX *sel= field->cached_table->select_lex;
+      SELECT_LEX *sel= field->field->table->pos_in_table_list->select_lex;
       if (sel->nest_level < aggr_level)
       {
         if (in_sum_func)
@@ -1110,18 +1110,19 @@ void Aggregator_distinct::endup()
       endup_done= TRUE;
     }
   }
-  else
-  {
-    /*
-      We don't have a tree only if 'setup()' hasn't been called;
-      this is the case of sql_select.cc:return_zero_rows.
-    */
-    if (tree)
-      table->field[0]->set_notnull();
-  }
 
+ /*
+   We don't have a tree only if 'setup()' hasn't been called;
+   this is the case of sql_executor.cc:return_zero_rows.
+ */
   if (tree && !endup_done)
   {
+   /*
+     All tree's values are not NULL.
+     Note that value of field is changed as we walk the tree, in
+     Aggregator_distinct::unique_walk_function, but it's always not NULL.
+   */
+   table->field[0]->set_notnull();
     /* go over the tree of distinct keys and calculate the aggregate value */
     use_distinct_values= TRUE;
     tree_walk_action func;
@@ -1417,7 +1418,7 @@ bool Item_sum_sum::add()
   {
     my_decimal value;
     const my_decimal *val= aggr->arg_val_decimal(&value);
-    if (!aggr->arg_is_null())
+    if (!aggr->arg_is_null(true))
     {
       my_decimal_add(E_DEC_FATAL_ERROR, dec_buffs + (curr_dec_buff^1),
                      val, dec_buffs + curr_dec_buff);
@@ -1428,7 +1429,7 @@ bool Item_sum_sum::add()
   else
   {
     sum+= aggr->arg_val_real();
-    if (!aggr->arg_is_null())
+    if (!aggr->arg_is_null(true))
       null_value= 0;
   }
   DBUG_RETURN(0);
@@ -1554,9 +1555,27 @@ double Aggregator_simple::arg_val_real()
 }
 
 
-bool Aggregator_simple::arg_is_null()
+bool Aggregator_simple::arg_is_null(bool use_null_value)
 {
-  return item_sum->args[0]->null_value;
+  Item **item= item_sum->args;
+  const uint item_count= item_sum->arg_count;
+  if (use_null_value)
+  {
+    for (uint i= 0; i < item_count; i++)
+    {
+      if (item[i]->null_value)
+        return true;
+    }
+  }
+  else
+  {
+    for (uint i= 0; i < item_count; i++)
+    {
+      if (item[i]->maybe_null && item[i]->is_null())
+        return true;
+    }
+  }
+  return false;
 }
 
 
@@ -1574,10 +1593,17 @@ double Aggregator_distinct::arg_val_real()
 }
 
 
-bool Aggregator_distinct::arg_is_null()
+bool Aggregator_distinct::arg_is_null(bool use_null_value)
 {
-  return use_distinct_values ? table->field[0]->is_null() :
-    item_sum->args[0]->null_value;
+  if (use_distinct_values)
+  {
+    const bool rc= table->field[0]->is_null();
+    DBUG_ASSERT(!rc); // NULLs are never stored in 'tree'
+    return rc;
+  }
+  return use_null_value ?
+    item_sum->args[0]->null_value :
+    (item_sum->args[0]->maybe_null && item_sum->args[0]->is_null());
 }
 
 
@@ -1595,11 +1621,8 @@ void Item_sum_count::clear()
 
 bool Item_sum_count::add()
 {
-  for (uint i=0; i<arg_count; i++)
-  {
-    if (args[i]->maybe_null && args[i]->is_null())
-      return 0;
-  }
+  if (aggr->arg_is_null(false))
+    return 0;
   count++;
   return 0;
 }
@@ -1691,7 +1714,7 @@ bool Item_sum_avg::add()
 {
   if (Item_sum_sum::add())
     return TRUE;
-  if (!aggr->arg_is_null())
+  if (!aggr->arg_is_null(true))
     count++;
   return FALSE;
 }