~drizzle-trunk/drizzle/development

/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright (C) 2009 Sun Microsystems

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; version 2 of the License.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

#ifndef DRIZZLED_OPTIMIZER_KEY_USE_H

#define DRIZZLED_OPTIMIZER_KEY_USE_H

namespace drizzled

{

namespace optimizer

{

class KeyUse 

{

public:

  KeyUse()

    :

      table(NULL),

      val(NULL),

      used_tables(0),

      key(0),

      keypart(0),

      optimize(0),

      keypart_map(0),

      ref_table_rows(0),

      null_rejecting(false),

      cond_guard(NULL)

  {}

  KeyUse(Table *in_table,

         Item *in_val,

         table_map in_used_tables,

         uint32_t in_key,

         uint32_t in_keypart,

         uint32_t in_optimize,

         key_part_map in_keypart_map,

         ha_rows in_ref_table_rows,

         bool in_null_rejecting,

         bool *in_cond_guard)

    :

      table(in_table),

      val(in_val),

      used_tables(in_used_tables),

      key(in_key),

      keypart(in_keypart),

      optimize(in_optimize),

      keypart_map(in_keypart_map),

      ref_table_rows(in_ref_table_rows),

      null_rejecting(in_null_rejecting),

      cond_guard(in_cond_guard)

  {}

  Table *getTable()

  {

    return table;

  }

  Item *getVal()

  {

    return val;

  }

  table_map getUsedTables()

  {

    return used_tables;

  }

  uint32_t getKey() const

  {

    return key;

  }

  uint32_t getKeypart() const

  {

    return keypart;

  }

  uint32_t getOptimizeFlags() const

  {

    return optimize;

  }

  key_part_map getKeypartMap()

  {

    return keypart_map;

  }

  ha_rows getTableRows() const

  {

    return ref_table_rows;

  }

  void setTableRows(ha_rows input)

  {

    ref_table_rows= input;

  }

  bool isNullRejected() const

  {

    return null_rejecting;

  }

  bool *getConditionalGuard()

  {

    return cond_guard;

  }

private:

  Table *table; /**< Pointer to the table this key belongs to */

  Item *val;	/**< or value if no field */

  table_map used_tables;

  uint32_t key;

  uint32_t keypart;

  uint32_t optimize; /**< 0, or KEY_OPTIMIZE_* */

  key_part_map keypart_map;

  ha_rows ref_table_rows;

  /**

   * If true, the comparison this value was created from will not be

   * satisfied if val has NULL 'value'.

   */

  bool null_rejecting;

  /**

   * !NULL - This KeyUse was created from an equality that was wrapped into

   *         an Item_func_trig_cond. This means the equality (and validity of

   *         this KeyUse element) can be turned on and off. The on/off state

   *         is indicted by the pointed value:

   *           *cond_guard == true <=> equality condition is on

   *           *cond_guard == false <=> equality condition is off

   *

   * NULL  - Otherwise (the source equality can't be turned off)

  */

  bool *cond_guard;

};

} /* end namespace optimizer */

} /* end namespace drizzled */

#endif /* DRIZZLED_OPTIMIZER_KEY_USE_H */