has_error field added to the item_sum class. This field ensures that query is terminated

if we get any error during the add function call. This is currently used only for the
percentile functions

Author: varunraiko

sql/item_sum.cc

@@ -441,6 +441,7 @@ Item_sum::Item_sum(THD *thd, List<Item> &list): Item_func_or_sum(thd, list)
   mark_as_sum_func();
   init_aggregator();
   list.empty();					// Fields are used
+  has_error= FALSE;
 }
 
 
@@ -452,7 +453,7 @@ Item_sum::Item_sum(THD *thd, Item_sum *item):
   Item_func_or_sum(thd, item),
   aggr_sel(item->aggr_sel),
   nest_level(item->nest_level), aggr_level(item->aggr_level),
-  quick_group(item->quick_group),
+  quick_group(item->quick_group), has_error(FALSE),
   orig_args(NULL)
 {
   if (arg_count <= 2)

sql/item_sum.h

@@ -367,6 +367,7 @@ class Item_sum :public Item_func_or_sum
   int8 max_arg_level;     /* max level of unbound column references          */
   int8 max_sum_func_level;/* max level of aggregation for embedded functions */
   bool quick_group;			/* If incremental update of fields */
+  bool has_error;
   /*
     This list is used by the check for mixing non aggregated fields and
     sum functions in the ONLY_FULL_GROUP_BY_MODE. We save all outer fields
@@ -388,19 +389,19 @@ class Item_sum :public Item_func_or_sum
 public:  
 
   void mark_as_sum_func();
-  Item_sum(THD *thd): Item_func_or_sum(thd), quick_group(1)
+  Item_sum(THD *thd): Item_func_or_sum(thd), quick_group(1), has_error(0)
   {
     mark_as_sum_func();
     init_aggregator();
   }
   Item_sum(THD *thd, Item *a): Item_func_or_sum(thd, a), quick_group(1),
-    orig_args(tmp_orig_args)
+    has_error(0), orig_args(tmp_orig_args)
   {
     mark_as_sum_func();
     init_aggregator();
   }
   Item_sum(THD *thd, Item *a, Item *b): Item_func_or_sum(thd, a, b),
-    quick_group(1), orig_args(tmp_orig_args)
+    quick_group(1), has_error(0), orig_args(tmp_orig_args)
   {
     mark_as_sum_func();
     init_aggregator();