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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, Inc.
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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_OUTER_REF_H
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#define DRIZZLED_ITEM_OUTER_REF_H
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#include "drizzled/item/ref.h"
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#include "drizzled/item/direct_ref.h"
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#include "drizzled/item/field.h"
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Class for outer fields.
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An object of this class is created when the select where the outer field was
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resolved is a grouping one. After it has been fixed the ref field will point
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to either an Item_ref or an Item_direct_ref object which will be used to
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See also comments for the fix_inner_refs() and the
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Item_field::fix_outer_field() functions.
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class Item_outer_ref :public Item_direct_ref
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/* The aggregate function under which this outer ref is used, if any. */
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Item_sum *in_sum_func;
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true <=> that the outer_ref is already present in the select list
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bool found_in_select_list;
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Item_outer_ref(Name_resolution_context *context_arg,
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Item_field *outer_field_arg)
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:Item_direct_ref(context_arg, 0, outer_field_arg->table_name,
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outer_field_arg->field_name),
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outer_ref(outer_field_arg), in_sum_func(0),
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found_in_select_list(0)
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Item_outer_ref(Name_resolution_context *context_arg, Item **item,
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const char *table_name_arg, const char *field_name_arg,
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bool alias_name_used_arg)
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:Item_direct_ref(context_arg, item, table_name_arg, field_name_arg,
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outer_ref(0), in_sum_func(0), found_in_select_list(1)
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void save_in_result_field(bool)
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outer_ref->save_org_in_field(result_field);
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bool fix_fields(Session *, Item **);
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void fix_after_pullout(Select_Lex *new_parent, Item **ref);
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table_map used_tables() const
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return (*ref)->const_item() ? 0 : OUTER_REF_TABLE_BIT;
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virtual Ref_Type ref_type() { return OUTER_REF; }
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} /* namespace drizzled */
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#endif /* DRIZZLED_ITEM_OUTER_REF_H */