Drizzled Public API Documentation

null.h
1 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
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3  *
4  * Copyright (C) 2008 Sun Microsystems, Inc.
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19 
20 #pragma once
21 
22 #include <drizzled/charset.h>
23 #include <drizzled/item/basic_constant.h>
24 
25 namespace drizzled {
26 
28 {
29 public:
30 
31  Item_null(const char *name_par=0)
32  {
33  maybe_null= null_value= true;
34  max_length= 0;
35  name= name_par ? name_par : "NULL";
36  fixed= 1;
37  collation.set(&my_charset_bin, DERIVATION_IGNORABLE);
38  }
39  Type type() const { return NULL_ITEM; }
40  bool eq(const Item *item, bool binary_cmp) const;
41  double val_real();
42  int64_t val_int();
43  String *val_str(String *str);
45  int save_in_field(Field *field, bool no_conversions);
46  int save_safe_in_field(Field *field);
47  void send(plugin::Client *client, String *str);
48  enum Item_result result_type () const { return STRING_RESULT; }
49  enum_field_types field_type() const { return DRIZZLE_TYPE_NULL; }
50  bool basic_const_item() const { return 1; }
51  Item *clone_item() { return new Item_null(name); }
52  bool is_null() { return true; }
53 
54  virtual void print(String *str);
55 
56  Item *safe_charset_converter(const charset_info_st * const tocs);
57 };
58 
60 {
61 public:
62  Field *result_field;
63  Item_null_result() : Item_null(), result_field(0) {}
64  bool is_result_field() { return result_field != 0; }
65  void save_in_result_field(bool no_conversions)
66  {
67  save_in_field(result_field, no_conversions);
68  }
69 };
70 
71 } /* namespace drizzled */
72 
const char * name
Definition: item.h:110
int64_t val_int()
Definition: null.cc:39
bool is_null()
Definition: null.h:52
bool fixed
Definition: item.h:120
TODO: Rename this file - func.h is stupid.
virtual void print(String *str)
Definition: null.cc:61
String * val_str(String *str)
Definition: null.cc:47
bool null_value
Definition: item.h:122
Definition: wakeup.h:27
bool maybe_null
Definition: item.h:121
double val_real()
Definition: null.cc:32
type::Decimal * val_decimal(type::Decimal *)
Definition: null.cc:55
void send(plugin::Client *client, String *str)
Definition: null.cc:112
int save_safe_in_field(Field *field)
Definition: null.cc:103
bool basic_const_item() const
Definition: null.h:50
bool eq(const Item *item, bool binary_cmp) const
Definition: null.cc:29
int save_in_field(Field *field, bool no_conversions)
Definition: null.cc:87