Drizzled Public API Documentation

sargable_param.h

00001 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
00002  *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
00003  *
00004  *  Copyright (C) 2009 Sun Microsystems, Inc.
00005  *
00006  *  This program is free software; you can redistribute it and/or modify
00007  *  it under the terms of the GNU General Public License as published by
00008  *  the Free Software Foundation; version 2 of the License.
00009  *
00010  *  This program is distributed in the hope that it will be useful,
00011  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
00012  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00013  *  GNU General Public License for more details.
00014  *
00015  *  You should have received a copy of the GNU General Public License
00016  *  along with this program; if not, write to the Free Software
00017  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
00018  */
00019 
00020 #pragma once
00021 
00022 namespace drizzled
00023 {
00024 namespace optimizer
00025 {
00026 
00040 class SargableParam
00041 {
00042 public:
00043   SargableParam()
00044     :
00045       field(NULL),
00046       arg_value(NULL),
00047       num_values(0)
00048   {}
00049 
00050   SargableParam(Field *in_field,
00051                 Item **in_arg_value,
00052                 uint32_t in_num_values)
00053     :
00054       field(in_field),
00055       arg_value(in_arg_value),
00056       num_values(in_num_values)
00057   {}
00058 
00059   SargableParam(const SargableParam &rhs)
00060     :
00061       field(rhs.field),
00062       arg_value(rhs.arg_value),
00063       num_values(rhs.num_values)
00064   {}
00065 
00066   SargableParam &operator=(const SargableParam &rhs)
00067   {
00068     if (this == &rhs)
00069     {
00070       return *this;
00071     }
00072     field= rhs.field;
00073     arg_value= rhs.arg_value;
00074     num_values= rhs.num_values;
00075     return *this;
00076   }
00077 
00078   Field *getField()
00079   {
00080     return field;
00081   }
00082 
00083   uint32_t getNumValues() const
00084   {
00085     return num_values;
00086   }
00087 
00088   bool isConstItem(uint32_t index)
00089   {
00090     return (arg_value[index]->const_item());
00091   }
00092 
00093 private:
00094 
00098   Field *field;
00099 
00103   Item **arg_value;
00104 
00108   uint32_t num_values;
00109 };
00110 
00111 } /* end namespace optimizer */
00112 
00113 } /* end namespace drizzled */
00114