Merge bk-internal.mysql.com:/home/bk/mysql-4.1

into mashka.mysql.fi:/home/my/mysql-tmp

1 files changed, 31 insertions, 44 deletions

diff --git a/sql/item_sum.cc b/sql/item_sum.cc
index 814612cfca8..2b31e15cb4c 100644
--- a/sql/item_sum.cc
+++ b/sql/item_sum.cc
@@ -70,6 +70,8 @@ void Item_sum::make_field(Send_field *tmp_field)
     tmp_field->db_name=(char*)"";
     tmp_field->org_table_name=tmp_field->table_name=(char*)"";
     tmp_field->org_col_name=tmp_field->col_name=name;
+    if (maybe_null)
+      tmp_field->flags&= ~NOT_NULL_FLAG;
   }
   else
     init_make_field(tmp_field, field_type());
@@ -197,7 +199,8 @@ Item_sum_hybrid::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
     max_length=item->max_length;
   }
   decimals=item->decimals;
-  maybe_null=item->maybe_null;
+  /* MIN/MAX can return NULL for empty set indepedent of the used column */
+  maybe_null= 1;
   unsigned_flag=item->unsigned_flag;
   collation.set(item->collation);
   result_field=0;
@@ -388,15 +391,15 @@ void Item_sum_variance::reset_field()
   }
 }
 
-void Item_sum_variance::update_field(int offset)
+void Item_sum_variance::update_field()
 {
   double nr,old_nr,old_sqr;
   longlong field_count;
   char *res=result_field->ptr;
 
-  float8get(old_nr,res+offset);
-  float8get(old_sqr,res+offset+sizeof(double));
-  field_count=sint8korr(res+offset+sizeof(double)*2);
+  float8get(old_nr, res);
+  float8get(old_sqr, res+sizeof(double));
+  field_count=sint8korr(res+sizeof(double)*2);
 
   nr=args[0]->val();
   if (!args[0]->null_value)
@@ -753,12 +756,12 @@ void Item_sum_bit::reset_field()
 ** calc next value and merge it with field_value
 */
 
-void Item_sum_sum::update_field(int offset)
+void Item_sum_sum::update_field()
 {
   double old_nr,nr;
   char *res=result_field->ptr;
 
-  float8get(old_nr,res+offset);
+  float8get(old_nr,res);
   nr=args[0]->val();
   if (!args[0]->null_value)
   {
@@ -769,12 +772,12 @@ void Item_sum_sum::update_field(int offset)
 }
 
 
-void Item_sum_count::update_field(int offset)
+void Item_sum_count::update_field()
 {
   longlong nr;
   char *res=result_field->ptr;
 
-  nr=sint8korr(res+offset);
+  nr=sint8korr(res);
   if (!args[0]->maybe_null)
     nr++;
   else
@@ -787,14 +790,14 @@ void Item_sum_count::update_field(int offset)
 }
 
 
-void Item_sum_avg::update_field(int offset)
+void Item_sum_avg::update_field()
 {
   double nr,old_nr;
   longlong field_count;
   char *res=result_field->ptr;
 
-  float8get(old_nr,res+offset);
-  field_count=sint8korr(res+offset+sizeof(double));
+  float8get(old_nr,res);
+  field_count=sint8korr(res+sizeof(double));
 
   nr=args[0]->val();
   if (!args[0]->null_value)
@@ -807,77 +810,65 @@ void Item_sum_avg::update_field(int offset)
   int8store(res,field_count);
 }
 
-void Item_sum_hybrid::update_field(int offset)
+void Item_sum_hybrid::update_field()
 {
   if (hybrid_type == STRING_RESULT)
-    min_max_update_str_field(offset);
+    min_max_update_str_field();
   else if (hybrid_type == INT_RESULT)
-    min_max_update_int_field(offset);
+    min_max_update_int_field();
   else
-    min_max_update_real_field(offset);
+    min_max_update_real_field();
 }
 
 
 void
-Item_sum_hybrid::min_max_update_str_field(int offset)
+Item_sum_hybrid::min_max_update_str_field()
 {
   String *res_str=args[0]->val_str(&value);
 
-  if (args[0]->null_value)
-    result_field->copy_from_tmp(offset);	// Use old value
-  else
+  if (!args[0]->null_value)
   {
     res_str->strip_sp();
-    result_field->ptr+=offset;			// Get old max/min
     result_field->val_str(&tmp_value,&tmp_value);
-    result_field->ptr-=offset;
 
     if (result_field->is_null() ||
 	(cmp_sign * sortcmp(res_str,&tmp_value,cmp_charset)) < 0)
       result_field->store(res_str->ptr(),res_str->length(),res_str->charset());
-    else
-    {						// Use old value
-      char *res=result_field->ptr;
-      memcpy(res,res+offset,result_field->pack_length());
-    }
     result_field->set_notnull();
   }
 }
 
 
 void
-Item_sum_hybrid::min_max_update_real_field(int offset)
+Item_sum_hybrid::min_max_update_real_field()
 {
   double nr,old_nr;
 
-  result_field->ptr+=offset;
   old_nr=result_field->val_real();
   nr=args[0]->val();
   if (!args[0]->null_value)
   {
-    if (result_field->is_null(offset) ||
+    if (result_field->is_null(0) ||
 	(cmp_sign > 0 ? old_nr > nr : old_nr < nr))
       old_nr=nr;
     result_field->set_notnull();
   }
-  else if (result_field->is_null(offset))
+  else if (result_field->is_null(0))
     result_field->set_null();
-  result_field->ptr-=offset;
   result_field->store(old_nr);
 }
 
 
 void
-Item_sum_hybrid::min_max_update_int_field(int offset)
+Item_sum_hybrid::min_max_update_int_field()
 {
   longlong nr,old_nr;
 
-  result_field->ptr+=offset;
   old_nr=result_field->val_int();
   nr=args[0]->val_int();
   if (!args[0]->null_value)
   {
-    if (result_field->is_null(offset))
+    if (result_field->is_null(0))
       old_nr=nr;
     else
     {
@@ -890,30 +881,29 @@ Item_sum_hybrid::min_max_update_int_field(int offset)
     }
     result_field->set_notnull();
   }
-  else if (result_field->is_null(offset))
+  else if (result_field->is_null(0))
     result_field->set_null();
-  result_field->ptr-=offset;
   result_field->store(old_nr);
 }
 
 
-void Item_sum_or::update_field(int offset)
+void Item_sum_or::update_field()
 {
   ulonglong nr;
   char *res=result_field->ptr;
 
-  nr=uint8korr(res+offset);
+  nr=uint8korr(res);
   nr|= (ulonglong) args[0]->val_int();
   int8store(res,nr);
 }
 
 
-void Item_sum_and::update_field(int offset)
+void Item_sum_and::update_field()
 {
   ulonglong nr;
   char *res=result_field->ptr;
 
-  nr=uint8korr(res+offset);
+  nr=uint8korr(res);
   nr&= (ulonglong) args[0]->val_int();
   int8store(res,nr);
 }
@@ -1931,6 +1921,3 @@ String* Item_func_group_concat::val_str(String* str)
   }
   return &result;
 }
-
-
-