Drizzled Public API Documentation

default_value.h

00001 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
00002  *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
00003  *
00004  *  Copyright (C) 2008 Sun Microsystems, Inc.
00005  *
00006  *  This program is free software; you can redistribute it and/or modify
00007  *  it under the terms of the GNU General Public License as published by
00008  *  the Free Software Foundation; version 2 of the License.
00009  *
00010  *  This program is distributed in the hope that it will be useful,
00011  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
00012  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00013  *  GNU General Public License for more details.
00014  *
00015  *  You should have received a copy of the GNU General Public License
00016  *  along with this program; if not, write to the Free Software
00017  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
00018  */
00019 
00020 #pragma once
00021 
00022 #include <drizzled/item/ident.h>
00023 #include <drizzled/item/field.h>
00024 
00025 namespace drizzled
00026 {
00027 
00028 class Item_default_value : public Item_field
00029 {
00030 public:
00031   Item *arg;
00032   Item_default_value(Name_resolution_context *context_arg)
00033     :Item_field(context_arg, (const char *)NULL, (const char *)NULL,
00034                (const char *)NULL),
00035      arg(NULL) {}
00036   Item_default_value(Name_resolution_context *context_arg, Item *a)
00037     :Item_field(context_arg, (const char *)NULL, (const char *)NULL,
00038                 (const char *)NULL),
00039      arg(a) {}
00040   enum Type type() const { return DEFAULT_VALUE_ITEM; }
00041   bool eq(const Item *item, bool binary_cmp) const;
00042   bool fix_fields(Session *, Item **);
00043   virtual void print(String *str);
00044   int save_in_field(Field *field_arg, bool no_conversions);
00045   table_map used_tables() const { return (table_map)0L; }
00046 
00047   bool walk(Item_processor processor, bool walk_subquery, unsigned char *args)
00048   {
00049     return arg->walk(processor, walk_subquery, args) ||
00050       (this->*processor)(args);
00051   }
00052 
00053   Item *transform(Item_transformer transformer, unsigned char *args);
00054 };
00055 
00056 } /* namespace drizzled */
00057