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/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
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* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
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* Copyright (C) 2008 Sun Microsystems
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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#ifndef DRIZZLED_ITEM_CACHE_H
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#define DRIZZLED_ITEM_CACHE_H
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#include "drizzled/item/ident.h"
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#include "drizzled/item/field.h"
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#include "drizzled/item/basic_constant.h"
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class Item_cache: public Item_basic_constant
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table_map used_table_map;
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Field that this object will get value from. This is set/used by
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index-based subquery engines to detect and remove the equality injected
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by IN->EXISTS transformation.
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For all other uses of Item_cache, cached_field doesn't matter.
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enum enum_field_types cached_field_type;
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example(0), used_table_map(0), cached_field(0), cached_field_type(DRIZZLE_TYPE_VARCHAR)
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Item_cache(enum_field_types field_type_arg):
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example(0), used_table_map(0), cached_field(0), cached_field_type(field_type_arg)
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void set_used_tables(table_map map) { used_table_map= map; }
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virtual bool allocate(uint32_t)
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virtual bool setup(Item *item)
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max_length= item->max_length;
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decimals= item->decimals;
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collation.set(item->collation);
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unsigned_flag= item->unsigned_flag;
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if (item->type() == FIELD_ITEM)
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cached_field= ((Item_field *)item)->field;
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virtual void store(Item *)= 0;
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enum Type type() const { return CACHE_ITEM; }
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enum_field_types field_type() const { return cached_field_type; }
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static Item_cache* get_cache(const Item *item);
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table_map used_tables() const { return used_table_map; }
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virtual void keep_array() {}
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virtual void print(String *str, enum_query_type query_type);
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bool eq_def(Field *field);
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bool eq(const Item *item, bool) const
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bool basic_const_item() const
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return test(example && example->basic_const_item());
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} /* namespace drizzled */
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#endif /* DRIZZLED_ITEM_CACHE_H */