Precision Math implementation

BitKeeper/etc/ignore:
  Added client/decimal.c client/my_decimal.cc client/my_decimal.h to the ignore list

1 files changed, 25 insertions, 0 deletions

diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index 89442d157c6..32c9e2a50f7 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -1340,6 +1340,9 @@ bool select_max_min_finder_subselect::send_data(List<Item> &items)
       case STRING_RESULT:
 	op= &select_max_min_finder_subselect::cmp_str;
 	break;
+      case DECIMAL_RESULT:
+        op= &select_max_min_finder_subselect::cmp_decimal;
+        break;
       case ROW_RESULT:
         // This case should never be choosen
 	DBUG_ASSERT(0);
@@ -1381,6 +1384,26 @@ bool select_max_min_finder_subselect::cmp_int()
        val1 < val2);
 }
 
+bool select_max_min_finder_subselect::cmp_decimal()
+{
+  String *val1, *val2, buf1, buf2;
+  Item *maxmin= ((Item_singlerow_subselect *)item)->el(0);
+  /*
+    as far as both operand is Item_cache buf1 & buf2 will not be used,
+    but added for safety
+  */
+  my_decimal cval, *cvalue= cache->val_decimal(&cval);
+  my_decimal mval, *mvalue= maxmin->val_decimal(&mval);
+  if (fmax)
+    return (cache->null_value && !maxmin->null_value) ||
+      (!cache->null_value && !maxmin->null_value &&
+       my_decimal_cmp(cvalue, mvalue) > 0) ;
+  else
+    return (maxmin->null_value && !cache->null_value) ||
+      (!cache->null_value && !maxmin->null_value &&
+       my_decimal_cmp(cvalue,mvalue) < 0);
+}
+
 bool select_max_min_finder_subselect::cmp_str()
 {
   String *val1, *val2, buf1, buf2;
@@ -1447,6 +1470,8 @@ int select_dumpvar::prepare(List<Item> &list, SELECT_LEX_UNIT *u)
       /*
         Item_func_set_user_var can't substitute something else on its place =>
         0 can be passed as last argument (reference on item)
+        Item_func_set_user_var can't be fixed after creation, so we do not
+        check xx->fixed
       */
       xx->fix_fields(thd, (TABLE_LIST*) thd->lex->select_lex.table_list.first,
 		     0);