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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_OPEN_TABLES_STATE_H
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#define DRIZZLED_OPEN_TABLES_STATE_H
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#include "drizzled/lock.h"
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Class that holds information about tables which were opened and locked
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by the thread. It is also used to save/restore this information in
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push_open_tables_state()/pop_open_tables_state().
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class Open_tables_state
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List of regular tables in use by this thread. Contains temporary and
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base tables that were opened with @see open_tables().
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List of temporary tables used by this thread. Contains user-level
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temporary tables, created with CREATE TEMPORARY TABLE, and
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internal temporary tables, created, e.g., to resolve a SELECT,
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or for an intermediate table used in ALTER.
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XXX Why are internal temporary tables added to this list?
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Table *temporary_tables;
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Table *derived_tables;
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During a MySQL session, one can lock tables in two modes: automatic
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or manual. In automatic mode all necessary tables are locked just before
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statement execution, and all acquired locks are stored in 'lock'
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member. Unlocking takes place automatically as well, when the
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Manual mode comes into play when a user issues a 'LOCK TABLES'
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statement. In this mode the user can only use the locked tables.
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Trying to use any other tables will give an error. The locked tables are
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stored in 'locked_tables' member. Manual locking is described in
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the 'LOCK_TABLES' chapter of the MySQL manual.
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See also lock_tables() for details.
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CREATE-SELECT keeps an extra lock for the table being
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created. This field is used to keep the extra lock available for
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lower level routines, which would otherwise miss that lock.
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DrizzleLock *extra_lock;
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uint32_t current_tablenr;
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This constructor serves for creation of Open_tables_state instances
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which are used as backup storage.
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Open_tables_state() { }
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virtual ~Open_tables_state() {}
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Open_tables_state(uint64_t version_arg);
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} /* namespace drizzled */
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#endif /* DRIZZLED_OPEN_TABLES_STATE_H */