fixed printing of sum(distinct ) & avg(distinct ) & cast(... as decimal) (BUG#7015, BUG#11387)

mysql-test/r/view.result:
  using sum(distinct ), cast(... as decimal) & avg(distinct ) in views
mysql-test/t/view.test:
  using sum(distinct ), cast(... as decimal) & avg(distinct ) in views
sql/item.h:
  Add a comment for Item::print
sql/item_func.cc:
  Use functype(), not func_name() for item equvalence detection
sql/item_func.h:
  Missed function typoes added
  Add a comment for Item_func::func_name()
  style fix
sql/item_strfunc.cc:
  Use functype(), not func_name() for item equvalence detection
sql/item_strfunc.h:
  Add missing func_name and func_type
sql/item_sum.cc:
  Item_sum func_name report beggining of function till first argument
sql/item_sum.h:
  Item_sum func_name report beggining of function till first argument
sql/item_timefunc.cc:
  Use functype(), not func_name() for item equvalence detection
sql/item_timefunc.h:
  Add missing func_name and func_type
sql/item_uniq.h:
  Add missing func_name

mysql-test/r/view.result

@@ -1726,3 +1726,20 @@ sum(a)
 drop procedure p1;
 drop view v1;
 drop table t1;
+create table t1 (s1 int);
+create view  v1 as select sum(distinct s1) from t1;
+select * from v1;
+sum(distinct s1)
+NULL
+drop view v1;
+create view  v1 as select avg(distinct s1) from t1;
+select * from v1;
+avg(distinct s1)
+NULL
+drop view v1;
+drop table t1;
+create view v1 as select cast(1 as decimal);
+select * from v1;
+cast(1 as decimal)
+1.00
+drop view v1;

mysql-test/t/view.test

@@ -1569,3 +1569,21 @@ drop procedure p1;
 drop view v1;
 drop table t1;
 
+#
+# using sum(distinct ) & avg(distinct ) in views (BUG#7015)
+#
+create table t1 (s1 int);
+create view  v1 as select sum(distinct s1) from t1;
+select * from v1;
+drop view v1;
+create view  v1 as select avg(distinct s1) from t1;
+select * from v1;
+drop view v1;
+drop table t1;
+
+#
+# using cast(... as decimal) in views (BUG#11387);
+#
+create view v1 as select cast(1 as decimal);
+select * from v1;
+drop view v1;

sql/item.h

@@ -468,6 +468,18 @@ public:
   */
   virtual bool const_during_execution() const 
   { return (used_tables() & ~PARAM_TABLE_BIT) == 0; }
+  /*
+    This is an essential method for correct functioning of VIEWS.
+    To save a view in an .frm file we need its unequivocal
+    definition in SQL that takes into account sql_mode and
+    environmental settings.  Currently such definition is restored
+    by traversing through the parsed tree of a view and
+    print()'ing SQL syntax of every node to a String buffer. This
+    method is used to print the SQL definition of an item. The
+    second use of this method is for EXPLAIN EXTENDED, to print
+    the SQL of a query after all optimizations of the parsed tree
+    have been done.
+  */
   virtual void print(String *str_arg) { str_arg->append(full_name()); }
   void print_item_w_name(String *);
   virtual void update_used_tables() {}

sql/item_func.cc

@@ -1061,6 +1061,14 @@ my_decimal *Item_decimal_typecast::val_decimal(my_decimal *dec)
 }
 
 
+void Item_decimal_typecast::print(String *str)
+{
+  str->append("cast(", 5);
+  args[0]->print(str);
+  str->append(" as decimal)", 12);
+}
+
+
 double Item_func_plus::real_op()
 {
   double value= args[0]->val_real() + args[1]->val_real();
@@ -4111,7 +4119,7 @@ bool Item_func_get_user_var::eq(const Item *item, bool binary_cmp) const
     return 1;					// Same item is same.
   /* Check if other type is also a get_user_var() object */
   if (item->type() != FUNC_ITEM ||
-      ((Item_func*) item)->func_name() != func_name())
+      ((Item_func*) item)->functype() != functype())
     return 0;
   Item_func_get_user_var *other=(Item_func_get_user_var*) item;
   return (name.length == other->name.length &&

sql/item_func.h

@@ -54,7 +54,8 @@ public:
 		  SP_POINTN,SP_GEOMETRYN,SP_INTERIORRINGN,
                   NOT_FUNC, NOT_ALL_FUNC,
                   NOW_FUNC, TRIG_COND_FUNC,
-                  GUSERVAR_FUNC};
+                  GUSERVAR_FUNC, COLLATE_FUNC,
+                  EXTRACT_FUNC, CHAR_TYPECAST_FUNC };
   enum optimize_type { OPTIMIZE_NONE,OPTIMIZE_KEY,OPTIMIZE_OP, OPTIMIZE_NULL,
                        OPTIMIZE_EQUAL };
   enum Type type() const { return FUNC_ITEM; }
@@ -123,7 +124,17 @@ public:
   virtual optimize_type select_optimize() const { return OPTIMIZE_NONE; }
   virtual bool have_rev_func() const { return 0; }
   virtual Item *key_item() const { return args[0]; }
-  virtual const char *func_name() const { return "?"; }
+  /*
+    This method is used for debug purposes to print the name of an
+    item to the debug log. The second use of this method is as
+    a helper function of print(), where it is applicable.
+    To suit both goals it should return a meaningful,
+    distinguishable and sintactically correct string.  This method
+    should not be used for runtime type identification, use enum
+    {Sum}Functype and Item_func::functype()/Item_sum::sum_func()
+    instead.
+  */
+  virtual const char *func_name() const= 0;
   virtual bool const_item() const { return const_item_cache; }
   inline Item **arguments() const { return args; }
   void set_arguments(List<Item> &list);
@@ -306,6 +317,8 @@ public:
   enum Item_result result_type () const { return DECIMAL_RESULT; }
   enum_field_types field_type() const { return MYSQL_TYPE_NEWDECIMAL; }
   void fix_length_and_dec() {};
+  const char *func_name() const { return "decimal_typecast"; }
+  void print(String *);
 };
 
 
@@ -506,7 +519,7 @@ public:
 
 class Item_func_acos :public Item_dec_func
 {
- public:
+public:
   Item_func_acos(Item *a) :Item_dec_func(a) {}
   double val_real();
   const char *func_name() const { return "acos"; }
@@ -514,7 +527,7 @@ class Item_func_acos :public Item_dec_func
 
 class Item_func_asin :public Item_dec_func
 {
- public:
+public:
   Item_func_asin(Item *a) :Item_dec_func(a) {}
   double val_real();
   const char *func_name() const { return "asin"; }
@@ -522,7 +535,7 @@ class Item_func_asin :public Item_dec_func
 
 class Item_func_atan :public Item_dec_func
 {
- public:
+public:
   Item_func_atan(Item *a) :Item_dec_func(a) {}
   Item_func_atan(Item *a,Item *b) :Item_dec_func(a,b) {}
   double val_real();
@@ -531,7 +544,7 @@ class Item_func_atan :public Item_dec_func
 
 class Item_func_cos :public Item_dec_func
 {
- public:
+public:
   Item_func_cos(Item *a) :Item_dec_func(a) {}
   double val_real();
   const char *func_name() const { return "cos"; }
@@ -539,7 +552,7 @@ class Item_func_cos :public Item_dec_func
 
 class Item_func_sin :public Item_dec_func
 {
- public:
+public:
   Item_func_sin(Item *a) :Item_dec_func(a) {}
   double val_real();
   const char *func_name() const { return "sin"; }
@@ -547,7 +560,7 @@ class Item_func_sin :public Item_dec_func
 
 class Item_func_tan :public Item_dec_func
 {
- public:
+public:
   Item_func_tan(Item *a) :Item_dec_func(a) {}
   double val_real();
   const char *func_name() const { return "tan"; }
@@ -634,7 +647,7 @@ class Item_func_units :public Item_real_func
 {
   char *name;
   double mul,add;
- public:
+public:
   Item_func_units(char *name_arg,Item *a,double mul_arg,double add_arg)
     :Item_real_func(a),name(name_arg),mul(mul_arg),add(add_arg) {}
   double val_real();
@@ -853,7 +866,7 @@ public:
 class Item_func_benchmark :public Item_int_func
 {
   ulong loop_count;
- public:
+public:
   Item_func_benchmark(ulong loop_count_arg,Item *expr)
     :Item_int_func(expr), loop_count(loop_count_arg)
   {}
@@ -868,7 +881,7 @@ class Item_func_benchmark :public Item_int_func
 
 class Item_udf_func :public Item_func
 {
- protected:
+protected:
   udf_handler udf;
 
 public:
@@ -1046,7 +1059,7 @@ class Item_func_get_lock :public Item_int_func
 class Item_func_release_lock :public Item_int_func
 {
   String value;
- public:
+public:
   Item_func_release_lock(Item *a) :Item_int_func(a) {}
   longlong val_int();
   const char *func_name() const { return "release_lock"; }
@@ -1058,7 +1071,7 @@ class Item_func_release_lock :public Item_int_func
 class Item_master_pos_wait :public Item_int_func
 {
   String value;
- public:
+public:
   Item_master_pos_wait(Item *a,Item *b) :Item_int_func(a,b) {}
   Item_master_pos_wait(Item *a,Item *b,Item *c) :Item_int_func(a,b,c) {}
   longlong val_int();

sql/item_strfunc.cc

@@ -2297,7 +2297,7 @@ bool Item_func_set_collation::eq(const Item *item, bool binary_cmp) const
     return 0;
   Item_func *item_func=(Item_func*) item;
   if (arg_count != item_func->arg_count ||
-      func_name() != item_func->func_name())
+      functype() != item_func->functype())
     return 0;
   Item_func_set_collation *item_func_sc=(Item_func_set_collation*) item;
   if (collation.collation != item_func_sc->collation.collation)

sql/item_strfunc.h

@@ -573,6 +573,7 @@ public:
     max_length=args[0]->max_length;
   }
   void print(String *str);
+  const char *func_name() const { return "cast_as_binary"; }
 };
 
 
@@ -648,6 +649,7 @@ public:
   void fix_length_and_dec();
   bool eq(const Item *item, bool binary_cmp) const;
   const char *func_name() const { return "collate"; }
+  enum Functype func_type() const { return COLLATE_FUNC; }
   void print(String *str);
   Item_field *filed_for_view_update()
   {

sql/item_sum.cc

@@ -86,7 +86,6 @@ void Item_sum::make_field(Send_field *tmp_field)
 void Item_sum::print(String *str)
 {
   str->append(func_name());
-  str->append('(');
   for (uint i=0 ; i < arg_count ; i++)
   {
     if (i)
@@ -2425,13 +2424,6 @@ longlong Item_sum_count_distinct::val_int()
 }
 
 
-void Item_sum_count_distinct::print(String *str)
-{
-  str->append("count(distinct ", 15);
-  args[0]->print(str);
-  str->append(')');
-}
-
 /****************************************************************************
 ** Functions to handle dynamic loadable aggregates
 ** Original source by: Alexis Mikhailov <root@medinf.chuvashia.su>
@@ -2466,6 +2458,20 @@ void Item_udf_sum::cleanup()
 }
 
 
+void Item_udf_sum::print(String *str)
+{
+  str->append(func_name());
+  str->append('(');
+  for (uint i=0 ; i < arg_count ; i++)
+  {
+    if (i)
+      str->append(',');
+    args[i]->print(str);
+  }
+  str->append(')');
+}
+
+
 Item *Item_sum_udf_float::copy_or_same(THD* thd)
 {
   return new (thd->mem_root) Item_sum_udf_float(thd, this);

sql/item_sum.h

@@ -81,7 +81,22 @@ public:
   virtual void update_field()=0;
   virtual bool keep_field_type(void) const { return 0; }
   virtual void fix_length_and_dec() { maybe_null=1; null_value=1; }
-  virtual const char *func_name() const { return "?"; }
+  /*
+    This method is used for debug purposes to print the name of an
+    item to the debug log. The second use of this method is as
+    a helper function of print(), where it is applicable.
+    To suit both goals it should return a meaningful,
+    distinguishable and sintactically correct string.  This method
+    should not be used for runtime type identification, use enum
+    {Sum}Functype and Item_func::functype()/Item_sum::sum_func()
+    instead.
+
+    NOTE: for Items inherited from Item_sum, func_name() return part of
+    function name till first argument (including '(') to make difference in
+    names for functions with 'distinct' clause and without 'distinct' and
+    also to make printing of items inherited from Item_sum uniform.
+  */
+  virtual const char *func_name() const= 0;
   virtual Item *result_item(Field *field)
     { return new Item_field(field);}
   table_map used_tables() const { return ~(table_map) 0; } /* Not used */
@@ -159,7 +174,7 @@ public:
   void reset_field();
   void update_field();
   void no_rows_in_result() {}
-  const char *func_name() const { return "sum"; }
+  const char *func_name() const { return "sum("; }
   Item *copy_or_same(THD* thd);
 };
 
@@ -200,7 +215,6 @@ public:
   enum Sumfunctype sum_func () const { return SUM_DISTINCT_FUNC; }
   void reset_field() {} // not used
   void update_field() {} // not used
-  const char *func_name() const { return "sum_distinct"; }
   virtual void no_rows_in_result() {}
   void fix_length_and_dec();
   enum Item_result result_type () const { return val.traits->type(); }
@@ -224,7 +238,7 @@ public:
   Item_sum_sum_distinct(Item *item_arg) :Item_sum_distinct(item_arg) {}
 
   enum Sumfunctype sum_func () const { return SUM_DISTINCT_FUNC; }
-  const char *func_name() const { return "sum_distinct"; }
+  const char *func_name() const { return "sum(distinct "; }
   Item *copy_or_same(THD* thd) { return new Item_sum_sum_distinct(thd, this); }
 };
 
@@ -243,7 +257,7 @@ public:
   void fix_length_and_dec();
   virtual void calculate_val_and_count();
   enum Sumfunctype sum_func () const { return AVG_DISTINCT_FUNC; }
-  const char *func_name() const { return "avg_distinct"; }
+  const char *func_name() const { return "avg(distinct "; }
   Item *copy_or_same(THD* thd) { return new Item_sum_avg_distinct(thd, this); }
 };
 
@@ -272,7 +286,7 @@ class Item_sum_count :public Item_sum_int
   void reset_field();
   void cleanup();
   void update_field();
-  const char *func_name() const { return "count"; }
+  const char *func_name() const { return "count("; }
   Item *copy_or_same(THD* thd);
 };
 
@@ -326,12 +340,11 @@ public:
   longlong val_int();
   void reset_field() { return ;}		// Never called
   void update_field() { return ; }		// Never called
-  const char *func_name() const { return "count_distinct"; }
+  const char *func_name() const { return "count(distinct "; }
   bool setup(THD *thd);
   void make_unique();
   Item *copy_or_same(THD* thd);
   void no_rows_in_result() {}
-  void print(String *str);
 };
 
 
@@ -389,7 +402,7 @@ public:
   Item *result_item(Field *field)
   { return new Item_avg_field(hybrid_type, this); }
   void no_rows_in_result() {}
-  const char *func_name() const { return "avg"; }
+  const char *func_name() const { return "avg("; }
   Item *copy_or_same(THD* thd);
   Field *create_tmp_field(bool group, TABLE *table, uint convert_blob_length);
 };
@@ -466,7 +479,7 @@ public:
   Item *result_item(Field *field)
   { return new Item_variance_field(this); }
   void no_rows_in_result() {}
-  const char *func_name() const { return "variance"; }
+  const char *func_name() const { return "variance("; }
   Item *copy_or_same(THD* thd);
   Field *create_tmp_field(bool group, TABLE *table, uint convert_blob_length);
   enum Item_result result_type () const { return hybrid_type; }
@@ -501,7 +514,7 @@ class Item_sum_std :public Item_sum_variance
   double val_real();
   Item *result_item(Field *field)
     { return new Item_std_field(this); }
-  const char *func_name() const { return "std"; }
+  const char *func_name() const { return "std("; }
   Item *copy_or_same(THD* thd);
   enum Item_result result_type () const { return REAL_RESULT; }
   enum_field_types field_type() const { return MYSQL_TYPE_DOUBLE;}
@@ -565,7 +578,7 @@ public:
   enum Sumfunctype sum_func () const {return MIN_FUNC;}
 
   bool add();
-  const char *func_name() const { return "min"; }
+  const char *func_name() const { return "min("; }
   Item *copy_or_same(THD* thd);
 };
 
@@ -578,7 +591,7 @@ public:
   enum Sumfunctype sum_func () const {return MAX_FUNC;}
 
   bool add();
-  const char *func_name() const { return "max"; }
+  const char *func_name() const { return "max("; }
   Item *copy_or_same(THD* thd);
 };
 
@@ -609,7 +622,7 @@ public:
   Item_sum_or(Item *item_par) :Item_sum_bit(item_par,LL(0)) {}
   Item_sum_or(THD *thd, Item_sum_or *item) :Item_sum_bit(thd, item) {}
   bool add();
-  const char *func_name() const { return "bit_or"; }
+  const char *func_name() const { return "bit_or("; }
   Item *copy_or_same(THD* thd);
 };
 
@@ -620,7 +633,7 @@ class Item_sum_and :public Item_sum_bit
   Item_sum_and(Item *item_par) :Item_sum_bit(item_par, ULONGLONG_MAX) {}
   Item_sum_and(THD *thd, Item_sum_and *item) :Item_sum_bit(thd, item) {}
   bool add();
-  const char *func_name() const { return "bit_and"; }
+  const char *func_name() const { return "bit_and("; }
   Item *copy_or_same(THD* thd);
 };
 
@@ -630,7 +643,7 @@ class Item_sum_xor :public Item_sum_bit
   Item_sum_xor(Item *item_par) :Item_sum_bit(item_par,LL(0)) {}
   Item_sum_xor(THD *thd, Item_sum_xor *item) :Item_sum_bit(thd, item) {}
   bool add();
-  const char *func_name() const { return "bit_xor"; }
+  const char *func_name() const { return "bit_xor("; }
   Item *copy_or_same(THD* thd);
 };
 
@@ -668,6 +681,7 @@ public:
   void reset_field() {};
   void update_field() {};
   void cleanup();
+  void print(String *str);
 };
 
 

sql/item_timefunc.cc

@@ -2158,7 +2158,7 @@ bool Item_extract::eq(const Item *item, bool binary_cmp) const
   if (this == item)
     return 1;
   if (item->type() != FUNC_ITEM ||
-      func_name() != ((Item_func*)item)->func_name())
+      functype() != ((Item_func*)item)->functype())
     return 0;
 
   Item_extract* ie= (Item_extract*)item;
@@ -2176,7 +2176,7 @@ bool Item_char_typecast::eq(const Item *item, bool binary_cmp) const
   if (this == item)
     return 1;
   if (item->type() != FUNC_ITEM ||
-      func_name() != ((Item_func*)item)->func_name())
+      functype() != ((Item_func*)item)->functype())
     return 0;
 
   Item_char_typecast *cast= (Item_char_typecast*)item;

sql/item_timefunc.h

@@ -637,6 +637,7 @@ class Item_extract :public Item_int_func
   Item_extract(interval_type type_arg, Item *a)
     :Item_int_func(a), int_type(type_arg) {}
   longlong val_int();
+  enum Functype functype() const { return EXTRACT_FUNC; }
   const char *func_name() const { return "extract"; }
   void fix_length_and_dec();
   bool eq(const Item *item, bool binary_cmp) const;
@@ -689,6 +690,7 @@ class Item_char_typecast :public Item_typecast
 public:
   Item_char_typecast(Item *a, int length_arg, CHARSET_INFO *cs_arg)
     :Item_typecast(a), cast_length(length_arg), cast_cs(cs_arg) {}
+  enum Functype functype() const { return CHAR_TYPECAST_FUNC; }
   bool eq(const Item *item, bool binary_cmp) const;
   const char *func_name() const { return "cast_as_char"; }
   const char* cast_type() const { return "char"; };
@@ -790,6 +792,7 @@ public:
     return (new Field_string(max_length, maybe_null, name, t_arg, &my_charset_bin));
   }
   void print(String *str);
+  const char *func_name() const { return "add_time"; }
 };
 
 class Item_func_timediff :public Item_str_func

sql/item_uniq.h

@@ -30,6 +30,7 @@ public:
   double val_real() { DBUG_ASSERT(fixed == 1); return 0.0; }
   void fix_length_and_dec() { decimals=0; max_length=6; }
   void print(String *str) { str->append("0.0", 3); }
+  const char *func_name() const { return "unique_users"; }
 };
 
 
@@ -58,4 +59,5 @@ public:
   }
   void print(String *str) { str->append("0.0", 3); }
   Field *create_tmp_field(bool group, TABLE *table, uint convert_blob_length);
+  const char *func_name() const { return "sum_unique_users"; }
 };