get_user_var.h

/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
 *
 *  Copyright (C) 2008 Sun Microsystems, Inc.
 *
 *  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; version 2 of the License.
 *
 *  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
 */

#pragma once

#include <drizzled/function/func.h>
#include <drizzled/lex_string.h>

namespace drizzled {

class Item_func_get_user_var :public Item_func
{
  user_var_entry *var_entry;
  Item_result m_cached_result_type;
  Session &session;

public:
  str_ref name; // keep it public
  Item_func_get_user_var(Session &session_arg, str_ref a) :
    Item_func(),
    m_cached_result_type(STRING_RESULT),
    session(session_arg),
    name(a)
  {}
  enum Functype functype() const { return GUSERVAR_FUNC; }
  str_ref get_name() { return name; }
  double val_real();
  int64_t val_int();
  type::Decimal *val_decimal(type::Decimal*);
  String *val_str(String* str);
  void fix_length_and_dec();
  virtual void print(String *str);
  enum Item_result result_type() const;
  /*
    We must always return variables as strings to guard against selects of type
    select @t1:=1,@t1,@t:="hello",@t from foo where (@t1:= t2.b)
  */
  const char *func_name() const { return "get_user_var"; }
  bool const_item() const;
  table_map used_tables() const
  { return const_item() ? 0 : RAND_TABLE_BIT; }
  bool eq(const Item *item, bool binary_cmp) const;
};

} /* namespace drizzled */