A lot of fixes to Precision math

Mostly about precision/decimals of the results of the operations


include/decimal.h:
  decimal interface changed a little
sql/field.cc:
  a lot of precision/decimals related changes to the Field_new_decimal
sql/field.h:
  Field_new_decimal interface changed
sql/ha_ndbcluster.cc:
  f->precision should be used here
sql/item.cc:
  precision/decimals counting related changes
sql/item.h:
  precision/decimals counting related changes
sql/item_cmpfunc.cc:
  precision/decimals counting related changes
sql/item_cmpfunc.h:
  precision/decimals counting related changes
sql/item_func.cc:
  precision/decimals counting related changes
sql/item_func.h:
  precision/decimals counting related changes
sql/item_sum.cc:
  precision/decimals counting related changes
sql/item_sum.h:
  precision/decimals counting related changes
sql/my_decimal.cc:
  precision/decimals counting related changes
sql/my_decimal.h:
  precision/decimals counting related changes
sql/mysqld.cc:
  precision/decimals counting related changes
sql/set_var.cc:
  precision/decimals counting related changes
sql/sp_head.cc:
  dbug_decimal_print was replaced with dbug_decimal_as_string
sql/sql_class.h:
  div_precincrement variable added
sql/sql_parse.cc:
  precision/decimals counting related changes
sql/sql_select.cc:
  precision/decimals counting related changes
sql/sql_show.cc:
  Field::representation_length was removed
strings/decimal.c:
  decimal_actual_fraction was introduced
BitKeeper/etc/logging_ok:
  Logging to logging@openlogging.org accepted

1 files changed, 11 insertions, 2 deletions

diff --git a/sql/item.h b/sql/item.h
index f762896ba34..e5ec68d606e 100644
--- a/sql/item.h
+++ b/sql/item.h
@@ -258,7 +258,7 @@ public:
   Item *next;
   uint32 max_length;
   uint name_length;                     /* Length of name */
-  uint8 marker,decimals;
+  uint8 marker, decimals;
   my_bool maybe_null;			/* If item may be null */
   my_bool null_value;			/* if item is null */
   my_bool unsigned_flag;
@@ -442,6 +442,9 @@ public:
   virtual cond_result eq_cmp_result() const { return COND_OK; }
   inline uint float_length(uint decimals_par) const
   { return decimals != NOT_FIXED_DEC ? (DBL_DIG+2+decimals_par) : DBL_DIG+8;}
+  virtual uint decimal_precision() const;
+  inline int decimal_int_part() const
+  { return my_decimal_int_part(decimal_precision(), decimals); }
   /* 
     Returns true if this is constant (during query execution, i.e. its value
     will not change until next fix_fields) and its value is known.
@@ -937,7 +940,7 @@ public:
     { max_length=length; fixed= 1; }
 #ifdef HAVE_LONG_LONG
   Item_int(longlong i,uint length=21) :value(i)
-    { max_length=length; fixed= 1;}
+    { max_length=length; fixed= 1; }
 #endif
   Item_int(const char *str_arg,longlong i,uint length) :value(i)
     { max_length=length; name=(char*) str_arg; fixed= 1; }
@@ -956,6 +959,7 @@ public:
   void cleanup() {}
   void print(String *str);
   Item_num *neg() { value= -value; return this; }
+  uint decimal_precision() const { return (uint)(max_length - test(value < 0)); }
 };
 
 
@@ -983,6 +987,7 @@ public:
   int save_in_field(Field *field, bool no_conversions);
   void print(String *str);
   Item_num *neg ();
+  uint decimal_precision() const { return max_length; }
 };
 
 
@@ -1022,6 +1027,7 @@ public:
     unsigned_flag= !decimal_value.sign();
     return this;
   }
+  uint decimal_precision() const { return decimal_value.precision(); }
 };
 
 class Item_float :public Item_num
@@ -1784,6 +1790,9 @@ protected:
   enum_field_types fld_type;
 
   void get_full_info(Item *item);
+
+  /* It is used to count decimal precision in join_types */
+  int prev_decimal_int_part;
 public:
   Item_type_holder(THD*, Item*);