1 #ifndef ITEM_ROW_INCLUDED
2 #define ITEM_ROW_INCLUDED
3 
4 /*
5    Copyright (c) 2002, 2013, Oracle and/or its affiliates.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; version 2 of the License.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program; if not, write to the Free Software
18    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
19 
20 /**
21   Row items used for comparing rows and IN operations on rows:
22 
23   @verbatim
24   (a, b, c) > (10, 10, 30)
25   (a, b, c) = (select c, d, e, from t1 where x=12)
26   (a, b, c) IN ((1,2,2), (3,4,5), (6,7,8)
27   (a, b, c) IN (select c, d, e, from t1)
28   @endverbatim
29 */
30 
31 
32 /**
33    Item which stores (x,y,...) and ROW(x,y,...).
34    Note that this can be recursive: ((x,y),(z,t)) is a ROW of ROWs.
35 */
36 class Item_row: public Item,
37                 private Item_args,
38                 private Used_tables_and_const_cache,
39                 private With_subquery_cache
40 {
41   table_map not_null_tables_cache;
42   /**
43     If elements are made only of constants, of which one or more are
44     NULL. For example, this item is (1,2,NULL), or ( (1,NULL), (2,3) ).
45   */
46   bool with_null;
47 public:
Item_row(THD * thd,List<Item> & list)48   Item_row(THD *thd, List<Item> &list):
49   Item(thd), Item_args(thd, list), not_null_tables_cache(0), with_null(0)
50   { }
Item_row(THD * thd,Item_row * row)51   Item_row(THD *thd, Item_row *row):
52     Item(thd), Item_args(thd, static_cast<Item_args*>(row)), Used_tables_and_const_cache(),
53     not_null_tables_cache(0), with_null(0)
54   { }
55 
with_subquery()56   bool with_subquery() const { DBUG_ASSERT(fixed); return m_with_subquery; }
type()57   enum Type type() const { return ROW_ITEM; };
type_handler()58   const Type_handler *type_handler() const { return &type_handler_row; }
59   void illegal_method_call(const char *);
is_null()60   bool is_null() { return null_value; }
make_send_field(THD * thd,Send_field *)61   void make_send_field(THD *thd, Send_field *)
62   {
63     illegal_method_call((const char*)"make_send_field");
64   };
val_real()65   double val_real()
66   {
67     illegal_method_call((const char*)"val");
68     return 0;
69   };
val_int()70   longlong val_int()
71   {
72     illegal_method_call((const char*)"val_int");
73     return 0;
74   };
val_str(String *)75   String *val_str(String *)
76   {
77     illegal_method_call((const char*)"val_str");
78     return 0;
79   };
val_decimal(my_decimal *)80   my_decimal *val_decimal(my_decimal *)
81   {
82     illegal_method_call((const char*)"val_decimal");
83     return 0;
84   };
get_date(MYSQL_TIME * ltime,ulonglong fuzzydate)85   bool get_date(MYSQL_TIME *ltime, ulonglong fuzzydate)
86   {
87     illegal_method_call((const char*)"get_date");
88     return true;
89   }
90   bool fix_fields(THD *thd, Item **ref);
91   void fix_after_pullout(st_select_lex *new_parent, Item **ref, bool merge);
92   void cleanup();
93   void split_sum_func(THD *thd, Ref_ptr_array ref_pointer_array,
94                       List<Item> &fields, uint flags);
used_tables()95   table_map used_tables() const { return used_tables_cache; };
const_item()96   bool const_item() const { return const_item_cache; };
update_used_tables()97   void update_used_tables()
98   {
99     used_tables_and_const_cache_init();
100     used_tables_and_const_cache_update_and_join(arg_count, args);
101   }
not_null_tables()102   table_map not_null_tables() const { return not_null_tables_cache; }
103   virtual void print(String *str, enum_query_type query_type);
104 
walk(Item_processor processor,bool walk_subquery,void * arg)105   bool walk(Item_processor processor, bool walk_subquery, void *arg)
106   {
107     if (walk_args(processor, walk_subquery, arg))
108       return true;
109     return (this->*processor)(arg);
110   }
111   Item *transform(THD *thd, Item_transformer transformer, uchar *arg);
112   bool eval_not_null_tables(void *opt_arg);
113 
cols()114   uint cols() const { return arg_count; }
element_index(uint i)115   Item* element_index(uint i) { return args[i]; }
addr(uint i)116   Item** addr(uint i) { return args + i; }
117   bool check_cols(uint c);
null_inside()118   bool null_inside() { return with_null; };
119   void bring_value();
120 
propagate_equal_fields(THD * thd,const Context & ctx,COND_EQUAL * cond)121   Item* propagate_equal_fields(THD *thd, const Context &ctx, COND_EQUAL *cond)
122   {
123     Item_args::propagate_equal_fields(thd, Context_identity(), cond);
124     return this;
125   }
126 
excl_dep_on_table(table_map tab_map)127   bool excl_dep_on_table(table_map tab_map)
128   {
129     return Item_args::excl_dep_on_table(tab_map);
130   }
131 
excl_dep_on_grouping_fields(st_select_lex * sel)132   bool excl_dep_on_grouping_fields(st_select_lex *sel)
133   {
134     return Item_args::excl_dep_on_grouping_fields(sel);
135   }
136 
check_vcol_func_processor(void * arg)137   bool check_vcol_func_processor(void *arg) {return FALSE; }
get_copy(THD * thd)138   Item *get_copy(THD *thd)
139   { return get_item_copy<Item_row>(thd, this); }
140   Item *build_clone(THD *thd);
141 };
142 
143 #endif /* ITEM_ROW_INCLUDED */
144