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934.2.2
by Jay Pipes
Forgot to add the new files... |
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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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*
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* Copyright (C) 2008-2009 Sun Microsystems
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*
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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; either version 2 of the License, or
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* (at your option) any later version.
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*
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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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*
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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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*/
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/**
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* @file
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*
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* Defines the API for index hints
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*/
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#ifndef DRIZZLED_INDEX_HINT_H
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#define DRIZZLED_INDEX_HINT_H
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/*
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String names used to print a statement with index hints.
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Keep in sync with index_hint_type.
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*/
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extern const char * index_hint_type_name[]; |
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typedef unsigned char index_clause_map; |
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enum index_hint_type |
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{
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INDEX_HINT_IGNORE, |
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INDEX_HINT_USE, |
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INDEX_HINT_FORCE
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};
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/*
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Bits in index_clause_map : one for each possible FOR clause in
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USE/FORCE/IGNORE INDEX index hint specification
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*/
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#define INDEX_HINT_MASK_JOIN (1)
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#define INDEX_HINT_MASK_GROUP (1 << 1)
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#define INDEX_HINT_MASK_ORDER (1 << 2)
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#define INDEX_HINT_MASK_ALL (INDEX_HINT_MASK_JOIN | INDEX_HINT_MASK_GROUP | \
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INDEX_HINT_MASK_ORDER)
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/* Single element of an USE/FORCE/IGNORE INDEX list specified as a SQL hint */
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class Index_hint : public Sql_alloc |
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{
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public: |
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/* The type of the hint : USE/FORCE/IGNORE */
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enum index_hint_type type; |
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/* Where the hit applies to. A bitmask of INDEX_HINT_MASK_<place> values */
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index_clause_map clause; |
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/*
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The index name. Empty (str=NULL) name represents an empty list
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USE INDEX () clause
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*/
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LEX_STRING key_name; |
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Index_hint (enum index_hint_type type_arg, index_clause_map clause_arg, |
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char *str, uint32_t length) : |
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type(type_arg), clause(clause_arg) |
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{
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key_name.str= str; |
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key_name.length= length; |
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}
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void print(Session *session, String *str); |
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};
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#endif /* DRIZZLED_INDEX_HINT_H */ |