core/sql/executor/ExTrieTable.h

/* -*-C++-*-
******************************************************************************
*
* File:         ExTrieTable.h
* RCS:          $Id
* Description:  ExTrieTable class declaration
* Created:      7/1/97
* Modified:     $Author
* Language:     C++
* Status:       $State
*
*
// @@@ 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
//
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// KIND, either express or implied.  See the License for the
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// @@@ END COPYRIGHT @@@
*
*
******************************************************************************
*/
#ifndef __ExTrieTable_h__
#define __ExTrieTable_h__

// Includes
//
#include "ex_god.h"

// External forward declarations
//
class NAMemory;

typedef char **ExTrie;

class ExTrieTable : public ExGod {
public:
  ExTrieTable(Int32 keySize, Int32 dataSize, Int32 memSize, NAMemory *heap);
  ~ExTrieTable();

  Int32 getMaximumNumberTuples() const { return maximumNumberTuples_; };
  Int32 getMinimumNumberTuples() const { return minimumNumberTuples_; };
  char *getData() const { return data_; };

  char *getReturnRow() const { 
    if(returnRow_ < numberTuples_)
      return rootTuple_ - returnRow_ * dataSize_; 
    return 0;
  };
  void advanceReturnRow() { returnRow_++; };
  void resetReturnRow() { returnRow_ = 0; };
  

  Int32 findOrAdd(char *key);

private:
  Int32 keySize_;
  Int32 dataSize_;
  Int32 memSize_;
  NAMemory *heap_;

  char *memory_;
  Int32 maximumNumberTuples_;
  Int32 minimumNumberTuples_;

  ExTrie rootTrie_;
  ExTrie nextTrie_;
  char *data_;

  char *rootTuple_;
  Int32 numberTuples_;
  Int32 returnRow_;
};

#endif