SCRUM

Default in UPDATE & SELECT

sql/field.h

@@ -78,7 +78,7 @@ public:
   virtual void reset_fields() {}
   virtual void set_default()
   {
-    my_ptrdiff_t offset = table->default_values - table->record[0];
+    my_ptrdiff_t offset = table->default_values() - table->record[0];
     memcpy(ptr, ptr + offset, pack_length());
     if (null_ptr)
       *null_ptr= ((*null_ptr & (uchar) ~null_bit) |

sql/item.cc

@@ -1121,15 +1121,20 @@ bool Item_ref::check_loop(uint id)
 
 bool Item_default_value::eq(const Item *item, bool binary_cmp) const
 {
-  return item->type() == DEFAULT_VALUE_ITEM && 
+  return item->type() == DEFAULT_ITEM && 
     ((Item_default_value *)item)->arg->eq(arg, binary_cmp);
 }
 
 bool Item_default_value::fix_fields(THD *thd, struct st_table_list *table_list, Item **items)
 {
+  if (!arg)
+    return false;
   bool res= arg->fix_fields(thd, table_list, items);
   if (res)
     return res;
+  /* arg->type() can be only REF_ITEM or FIELD_ITEM for it defined as
+   simple_ident in sql_yacc.yy
+  */
   if (arg->type() == REF_ITEM)
   {
     Item_ref *ref= (Item_ref *)arg;
@@ -1144,7 +1149,7 @@ bool Item_default_value::fix_fields(THD *thd, struct st_table_list *table_list,
   if (!def_field)
     return 1;
   memcpy(def_field, field_arg->field, field_arg->field->size_of());
-  def_field->move_field(def_field->table->default_values - 
+  def_field->move_field(def_field->table->default_values() - 
 			def_field->table->record[0]);
   set_field(def_field);
   return 0;
@@ -1152,7 +1157,11 @@ bool Item_default_value::fix_fields(THD *thd, struct st_table_list *table_list,
 
 void Item_default_value::print(String *str)
 {
-  str->append("default(");
+  if (!arg)
+  {
+    str->append("DEFAULT");
+  }
+  str->append("DEFAULT(");
   arg->print(str);
   str->append(')');
 }

sql/item.h

@@ -36,8 +36,8 @@ public:
 	     COPY_STR_ITEM, FIELD_AVG_ITEM, DEFAULT_ITEM,
 	     PROC_ITEM,COND_ITEM, REF_ITEM, FIELD_STD_ITEM, 
 	     FIELD_VARIANCE_ITEM, CONST_ITEM,
-             SUBSELECT_ITEM, ROW_ITEM, CACHE_ITEM,
-             DEFAULT_VALUE_ITEM};
+             SUBSELECT_ITEM, ROW_ITEM, CACHE_ITEM};
+
   enum cond_result { COND_UNDEF,COND_OK,COND_TRUE,COND_FALSE };
 
   String str_value;			/* used to store value */
@@ -369,26 +369,6 @@ public:
   void print(String *str);
 };
 
-
-/* For INSERT ... VALUES (DEFAULT) */
-
-class Item_default :public Item
-{
-public:
-  Item_default() { name= (char*) "DEFAULT"; }
-  enum Type type() const { return DEFAULT_ITEM; }
-  int save_in_field(Field *field, bool no_conversions)
-  {
-    field->set_default();
-    return 0;
-  }
-  virtual double val() { return 0.0; }
-  virtual longlong val_int() { return 0; }
-  virtual String *val_str(String *str) { return 0; }
-  bool basic_const_item() const { return 1; }
-};
-
-
 /* for show tables */
 
 class Item_datetime :public Item_string
@@ -669,9 +649,11 @@ class Item_default_value : public Item_field
 {
 public:
   Item *arg;
+  Item_default_value() :
+    Item_field((const char *)NULL, (const char *)NULL, (const char *)NULL), arg(NULL) {}
   Item_default_value(Item *a) : 
     Item_field((const char *)NULL, (const char *)NULL, (const char *)NULL), arg(a) {}
-  enum Type type() const { return DEFAULT_VALUE_ITEM; }
+  enum Type type() const { return DEFAULT_ITEM; }
   bool eq(const Item *item, bool binary_cmp) const;
   bool fix_fields(THD *, struct st_table_list *, Item **);
   bool check_loop(uint id)
@@ -680,6 +662,22 @@ public:
   }
   void set_outer_resolving() { arg->set_outer_resolving(); }
   void print(String *str);
+  virtual bool basic_const_item() const { return true; }
+  int save_in_field(Field *field, bool no_conversions)
+  {
+    if (!arg)
+    {
+      field->set_default();
+      return 0;
+    }
+    return Item_field::save_in_field(field, no_conversions);
+  }
+  table_map used_tables() const
+  { 
+    if (!arg)
+      return (table_map) 0L; 
+    return Item_field::used_tables();
+  }
 };
 
 class Item_cache: public Item

sql/sql_yacc.yy

@@ -1831,8 +1831,10 @@ optional_braces:
 	| '(' ')' {};
 
 /* all possible expressions */
-expr:	expr_expr	{ $$= $1; }
-	| simple_expr	{ $$= $1; };
+expr:	
+	expr_expr	{ $$= $1; }
+	| simple_expr	{ $$= $1; }
+	;
 
 comp_op:  EQ		{ $$ = &comp_eq_creator; }
 	| GE		{ $$ = &comp_ge_creator; }
@@ -1848,7 +1850,7 @@ all_or_any: ALL     { $$ = 1; }
 
 /* expressions that begin with 'expr' */
 expr_expr:
-	  expr IN_SYM '(' expr_list ')'
+	 expr IN_SYM '(' expr_list ')'
 	  { $$= new Item_func_in($1,*$4); }
 	| expr NOT IN_SYM '(' expr_list ')'
 	  { $$= new Item_func_not(new Item_func_in($1,*$5)); }
@@ -2055,10 +2057,10 @@ simple_expr:
 	  { $$= new Item_func_conv_charset($3,$5); }
 	| CONVERT_SYM '(' expr ',' expr ',' expr ')'
 	  { $$= new Item_func_conv_charset3($3,$7,$5); }
-	| FUNC_ARG0 '(' ')'
-	  { $$= ((Item*(*)(void))($1.symbol->create_func))();}
 	| DEFAULT '(' simple_ident ')'
 	  { $$= new Item_default_value($3); }
+	| FUNC_ARG0 '(' ')'
+	  { $$= ((Item*(*)(void))($1.symbol->create_func))();}
 	| FUNC_ARG1 '(' expr ')'
 	  { $$= ((Item*(*)(Item*))($1.symbol->create_func))($3);}
 	| FUNC_ARG2 '(' expr ',' expr ')'
@@ -3122,7 +3124,7 @@ values:
 
 expr_or_default:
 	expr	  { $$= $1;}
-	| DEFAULT {$$= new Item_default(); }
+	| DEFAULT {$$= new Item_default_value(); }
 	;
 
 opt_insert_update:

sql/table.cc

@@ -261,8 +261,6 @@ int openfrm(const char *name, const char *alias, uint db_stat, uint prgflag,
       outparam->record[1]=outparam->record[0]; /* purecov: inspected */
   }
   
-  outparam->default_values= outparam->record[2];
-
   VOID(my_seek(file,pos,MY_SEEK_SET,MYF(0)));
   if (my_read(file,(byte*) head,288,MYF(MY_NABP))) goto err_not_open;
   if (crypted)

sql/table.h

@@ -54,7 +54,6 @@ struct st_table {
   Field_blob **blob_field;		/* Pointer to blob fields */
   HASH	name_hash;			/* hash of field names */
   byte *record[3];			/* Pointer to records */
-  byte *default_values;
   uint fields;				/* field count */
   uint reclength;			/* Recordlength */
   uint rec_buff_length;
@@ -137,6 +136,7 @@ struct st_table {
   uint          derived_select_number;   
   THD		*in_use;		/* Which thread uses this */
   struct st_table *next,*prev;
+  byte *default_values() { return record[2]; }
 };