| /********************************************************************** |
| // @@@ START COPYRIGHT @@@ |
| // |
| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you under the Apache License, Version 2.0 (the |
| // "License"); you may not use this file except in compliance |
| // with the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, |
| // software distributed under the License is distributed on an |
| // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| // KIND, either express or implied. See the License for the |
| // specific language governing permissions and limitations |
| // under the License. |
| // |
| // @@@ END COPYRIGHT @@@ |
| **********************************************************************/ |
| #ifndef QUERYREWERITEHANDLER_H |
| #define QUERYREWERITEHANDLER_H |
| /* -*-C++-*- |
| ************************************************************************** |
| * |
| * File: QueryRewriteHandler.h |
| * Description: MvQueryRewriteHandler class and methods |
| * Created: 02/14/2008 |
| * Language: C++ |
| * |
| ************************************************************************** |
| */ |
| |
| #include "Analyzer.h" |
| #include "XMLUtil.h" |
| |
| class QRMVDescriptor; |
| class QRXmlMessageObj; |
| |
| //============================================================================ |
| class MvQueryRewriteHandler : public NABasicObject |
| { |
| public: |
| MvQueryRewriteHandler(CollHeap* heap) |
| : mvName_(heap), |
| mvDescriptor_(NULL), |
| formatXml_(TRUE), |
| warningMessage_(heap) |
| {} |
| |
| // Methods called by CatMan during CREATE MV |
| QRMVDescriptorPtr getMvDescriptor() { return mvDescriptor_; } |
| |
| // Methods called by the Analyzer |
| void createMvDescriptor(QueryAnalysis* qa, RelExpr* expr, NAString& warningMessage); |
| RelExpr* handleMvQueryRewrite(QueryAnalysis* qa, RelExpr* expr, NAString& warningMessage); |
| |
| void dumpToFile(const char* fileName, const char* data); |
| //void dumpAnalysisToFile(QueryAnalysis* qa, RelExpr* expr); |
| |
| /** |
| * Determines whether query rewrite is worth pursuing for the current query. |
| * This decision is based on the nature and complexity of the query. |
| * |
| * @param rootExpr The pointer to the query root node. |
| * @return \c TRUE iff the query appears likely to benefit from looking for |
| * MVs to use in rewriting it. |
| */ |
| static NABoolean rewriteWorthTrying(RelRoot* rootExpr); |
| |
| NABoolean isMvqrSupportedForMV(QueryAnalysis* qa, RelExpr* expr, NAString& warningMessage); |
| |
| NAString& getWarningMessage() |
| { |
| return warningMessage_; |
| } |
| |
| protected: |
| RelRoot* handleAnalyzeOnlyQuery(RelRoot* rootExpr, NAString* xmlText); |
| RelRoot* handleAnalyzeOnlyQuery(RelRoot* rootExpr, const char* excuse); |
| |
| private: |
| // Details about the MV, to be written into the descriptor |
| NAString mvName_; |
| NABoolean isIncremental_; |
| NABoolean isImmediate_; |
| |
| QRMVDescriptorPtr mvDescriptor_; |
| NABoolean formatXml_; |
| XMLString* xmlText_; |
| NAString warningMessage_; |
| }; // MvQueryRewriteHandler |
| |
| #endif // QUERYREWERITEHANDLER_H |