| /********************************************************************** |
| // @@@ 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 _RU_MULTI_TXN_CONTEXT_H_ |
| #define _RU_MULTI_TXN_CONTEXT_H_ |
| |
| /* - |
| *-C++-*- |
| ****************************************************************************** |
| * |
| * File: RuMultiTxnContext.h |
| * Description: Definition of class CRUMultiTxnContext. |
| * |
| * Created: 08/17/2000 |
| * Language: C++ |
| * |
| * |
| ****************************************************************************** |
| */ |
| |
| //--------------------------------------------------------------------------// |
| // The purpose of this class is to create a stack abstract to the rows in the |
| // context log. |
| // |
| // Prior to any use of this class the user must call the ReadRowsFromContextUMD() |
| // function. |
| // |
| //--------------------------------------------------------------------------// |
| |
| #include "RuSQLStaticStatementContainer.h" |
| |
| class REFRESH_LIB_CLASS CRUMultiTxnContext { |
| public: |
| |
| //----------------------------------// |
| // Public Members |
| //----------------------------------// |
| public: |
| |
| virtual ~CRUMultiTxnContext() {} |
| |
| public: |
| |
| BOOL IsEmpty() const |
| { |
| return const_cast<CRUMultiTxnContext*>(this)-> |
| stack_.IsEmpty(); |
| } |
| |
| Int32 GetNumOfRows() const |
| { |
| return const_cast<CRUMultiTxnContext*>(this)-> |
| stack_.GetCount(); |
| } |
| |
| public: |
| |
| enum { ROW_DOES_NOT_EXIST = -1 }; |
| |
| // This function return ROW_DOES_NOT_EXIST if no such row exists |
| // index == 0 is the top row in the stack |
| TInt32 GetRowByIndex(Lng32 index); |
| TInt32 GetTargetEpochOfFirstRow() { return GetRowByIndex(0); } |
| TInt32 GetTargetEpochOfSecondRow() { return GetRowByIndex(1); } |
| |
| |
| public: |
| |
| // Read the "@EPOCH" column from the context table |
| void ReadRowsFromContextLog(CDMPreparedStatement *readStmt); |
| |
| // This function Adds a catchup line to the context |
| void Push(TInt32 epoch) |
| { |
| stack_.AddHead(epoch); |
| } |
| |
| void Pop() |
| { |
| stack_.RemoveHead(); |
| } |
| |
| //----------------------------------// |
| // Private Members |
| //----------------------------------// |
| |
| private: |
| // The rows of the context table are orderd when retrieved by begin_epoch desc |
| // so it allows us to look at the rows as a stack of context rows |
| CDSList<TInt32> stack_; |
| |
| }; |
| |
| #endif |