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/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
*
* Copyright (C) 2010 Padraig O'Sullivan
*
* Authors:
*
* Padraig O'Sullivan <posullivan@akibainc.com>
*
* 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_PLUGIN_QUERY_REWRITE_H
#define DRIZZLED_PLUGIN_QUERY_REWRITE_H
#include "drizzled/atomics.h"
#include "drizzled/plugin/plugin.h"
/**
* @file Defines the API for a QueryRewriter.
*/
namespace drizzled
{
namespace plugin
{
/**
* Class which rewrites queries
*/
class QueryRewriter : public Plugin
{
public:
explicit QueryRewriter(std::string name_arg)
:
Plugin(name_arg, "QueryRewriter")
{}
virtual ~QueryRewriter() {}
/**
* Rewrite a query in the form of a std::string
*
* @param[in] schema the schema the current session is in
* @param[out] to_rewrite string representing the query to rewrite
*/
virtual void rewrite(const std::string &schema, std::string &to_rewrite)= 0;
static bool addPlugin(QueryRewriter *in_rewriter);
static void removePlugin(QueryRewriter *in_rewriter);
/**
* Take a query to be rewritten and go through all the rewriters that are registered as plugins
* and let the enabled ones rewrite they query.
* TODO: does it make sense to have multiple rewriters?
*
* @param[in] schema the schema the current session is
* @param[out] to_rewrite string representing the query to rewrite
*/
static void rewriteQuery(const std::string &schema, std::string &to_rewrite);
private:
QueryRewriter();
QueryRewriter(const QueryRewriter&);
QueryRewriter& operator=(const QueryRewriter&);
};
} /* namespace plugin */
} /* namespace drizzled */
#endif /* DRIZZLED_PLUGIN_QUERY_REWRITE_H */
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