Drizzled Public API Documentation

insert_value.h
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19 
20 #pragma once
21 
22 #include <drizzled/item/field.h>
23 
24 namespace drizzled {
25 
26 /*
27  Item_insert_value -- an implementation of VALUES() function.
28  You can use the VALUES(col_name) function in the UPDATE clause
29  to refer to column values from the INSERT portion of the INSERT
30  ... UPDATE statement. In other words, VALUES(col_name) in the
31  UPDATE clause refers to the value of col_name that would be
32  inserted, had no duplicate-key conflict occurred.
33  In all other places this function returns NULL.
34 */
35 
37 {
38 public:
39  Item *arg;
41  : Item_field(context_arg, NULL, NULL, NULL),
42  arg(a) {}
43  bool eq(const Item *item, bool binary_cmp) const;
44  bool fix_fields(Session *, Item **);
45  virtual void print(String *str);
46  int save_in_field(Field *field_arg, bool no_conversions)
47  {
48  return Item_field::save_in_field(field_arg, no_conversions);
49  }
50  /*
51  We use RAND_TABLE_BIT to prevent Item_insert_value from
52  being treated as a constant and precalculated before execution
53  */
54  table_map used_tables() const { return RAND_TABLE_BIT; }
55 
56  bool walk(Item_processor processor, bool walk_subquery, unsigned char *args)
57  {
58  return arg->walk(processor, walk_subquery, args) || (this->*processor)(args);
59  }
60 };
61 
62 } /* namespace drizzled */
63 
TODO: Rename this file - func.h is stupid.
table_map used_tables() const
Definition: insert_value.h:54
bool fix_fields(Session *, Item **)
Definition: insert_value.cc:38
virtual void print(String *str)
Definition: insert_value.cc:89
bool eq(const Item *item, bool binary_cmp) const
Definition: insert_value.cc:32