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/* - mode: c++ c-basic-offset: 2; indent-tabs-mode: nil; -*-
* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
*
* Copyright (C) 2008 MySQL
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef DRIZZLED_FIELD_NULL_H
#define DRIZZLED_FIELD_NULL_H
#include <drizzled/field/str.h>
namespace drizzled
{
/*
* Everything saved in this will disappear. It will always return NULL
*/
class Field_null :public Field_str
{
static unsigned char null[1];
public:
using Field::store;
using Field::val_str;
using Field::cmp;
using Field::val_int;
Field_null(unsigned char *ptr_arg,
uint32_t len_arg,
const char *field_name_arg,
const CHARSET_INFO * const cs)
:Field_str(ptr_arg,
len_arg,
null,
1,
field_name_arg,
cs)
{}
enum_field_types type() const
{
return DRIZZLE_TYPE_NULL;
}
int store(const char *, uint32_t, const CHARSET_INFO * const)
{
null[0]= 1;
return 0;
}
int store(double)
{
null[0]= 1;
return 0;
}
int store(int64_t, bool)
{
null[0]= 1;
return 0;
}
int store_decimal(const type::Decimal *)
{
null[0]= 1;
return 0;
}
int reset(void)
{
return 0;
}
double val_real(void)
{
return 0.0;
}
int64_t val_int(void)
{
return 0;
}
type::Decimal *val_decimal(type::Decimal *)
{
return 0;
}
String *val_str(String *, String *value2)
{
value2->length(0);
return value2;
}
int cmp(const unsigned char *, const unsigned char *)
{
return 0;
}
void sort_string(unsigned char *, uint32_t)
{}
uint32_t pack_length() const
{
return 0;
}
void sql_type(String &str) const;
uint32_t size_of() const
{
return sizeof(*this);
}
uint32_t max_display_length()
{
return 4;
}
};
} /* namespace drizzled */
#endif /* DRIZZLED_FIELD_NULL_H */
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