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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) 2008-2009 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_OPTIMIZER_QUICK_ROR_INTERSECT_SELECT_H
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#define DRIZZLED_OPTIMIZER_QUICK_ROR_INTERSECT_SELECT_H
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#include "drizzled/optimizer/range.h"
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Rowid-Ordered Retrieval (ROR) index intersection quick select.
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This quick select produces intersection of row sequences returned
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by several QuickRangeSelects it "merges".
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All merged QuickRangeSelects must return rowids in rowid order.
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QuickRorIntersectSelect will return rows in rowid order, too.
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All merged quick selects retrieve {rowid, covered_fields} tuples (not full
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QuickRorIntersectSelect retrieves full records if it is not being used
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by QuickRorIntersectSelect and all merged quick selects together don't
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cover needed all fields.
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If one of the merged quick selects is a Clustered PK range scan, it is
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used only to filter rowid sequence produced by other merged quick selects.
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class QuickRorIntersectSelect : public QuickSelectInterface
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QuickRorIntersectSelect(Session *session,
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bool retrieve_full_rows,
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MEM_ROOT *parent_alloc);
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~QuickRorIntersectSelect();
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* Do post-constructor initialization.
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* QuickRorIntersectSelect::init()
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* @retval other Error code
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* Initialize quick select for row retrieval.
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* @retval other Error code
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* Retrieve next record.
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* QuickRorIntersectSelect::get_next()
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* Invariant on enter/exit: all intersected selects have retrieved all index
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* records with rowid <= some_rowid_val and no intersected select has
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* retrieved any index records with rowid > some_rowid_val.
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* We start fresh and loop until we have retrieved the same rowid in each of
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* the key scans or we got an error.
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* If a Clustered PK scan is present, it is used only to check if row
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* satisfies its condition (and never used for row retrieval).
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* @retval other - Error code if any error occurred.
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bool reverse_sorted() const
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bool unique_key_range() const
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return QS_TYPE_ROR_INTERSECT;
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void add_keys_and_lengths(String *key_names, String *used_lengths);
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void add_info_string(String *str);
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bool is_keys_used(const MyBitmap *fields);
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* Initialize this quick select to be a part of a ROR-merged scan.
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* QuickRorIntersectSelect::init_ror_merged_scan()
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* reuse_handler If true, use head->cursor, otherwise create separate
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* @retval other error code
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int init_ror_merged_scan(bool reuse_handler);
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* Add a merged quick select to this ROR-intersection quick select.
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* QuickRorIntersectSelect::push_quick_back()
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* quick Quick select to be added. The quick select must return
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* rows in rowid order.
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* This call can only be made before init() is called.
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* @retval true Out of memory.
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bool push_quick_back(QuickRangeSelect *quick_sel_range);
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* Range quick selects this intersection consists of, not including
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std::vector<QuickRangeSelect *> quick_selects;
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* Merged quick select that uses Clustered PK, if there is one. This quick
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* select is not used for row retrieval, it is used for row retrieval.
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QuickRangeSelect *cpk_quick;
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MEM_ROOT alloc; /**< Memory pool for this and merged quick selects data. */
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Session *session; /**< Pointer to the current session */
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bool need_to_fetch_row; /**< if true, do retrieve full table records. */
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/** in top-level quick select, true if merged scans where initialized */
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} /* namespace optimizer */
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} /* namespace drizzled */
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#endif /* DRIZZLED_OPTIMIZER_QUICK_ROR_INTERSECT_SELECT_H */
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drizzled/optimizer/quick_ror_intersect_select.h
