TableDescriptor.h

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/*
 * Copyright 2017 MapD Technologies, Inc.
 *
 * Licensed 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.
 */

#ifndef TABLE_DESCRIPTOR_H
#define TABLE_DESCRIPTOR_H

#include <cstdint>
#include <string>
#include "../DataMgr/MemoryLevel.h"
#include "../Fragmenter/AbstractFragmenter.h"
#include "../Shared/sqldefs.h"

struct TableDescriptor {
  int32_t tableId; 
  int32_t shard;
  std::string tableName; 
  int32_t userId;
  int32_t nColumns;
  bool isView;
  std::string viewSQL;
  std::string fragments;  // placeholder for fragmentation information
  Fragmenter_Namespace::FragmenterType
      fragType;            // fragmentation type. Only INSERT_ORDER is supported now.
  int32_t maxFragRows;     // max number of rows per fragment
  int64_t maxChunkSize;    // max number of rows per fragment
  int32_t fragPageSize;    // page size
  int64_t maxRows;         // max number of rows in the table
  std::string partitions;  // distributed partition scheme
  std::string
      keyMetainfo;  // meta-information about shard keys and shared dictionary, as JSON

  Fragmenter_Namespace::AbstractFragmenter*
      fragmenter;  // point to fragmenter object for the table.  it's instantiated upon
                   // first use.
  int32_t
      nShards;  // # of shards, i.e. physical tables for this logical table (default: 0)
  int shardedColumnId;  // Id of the column to be sharded on
  int sortedColumnId;   // Id of the column to be sorted on
  Data_Namespace::MemoryLevel persistenceLevel;
  bool hasDeletedCol;  // Does table has a delete col, Yes (VACUUM = DELAYED)
                       //                              No  (VACUUM = IMMEDIATE)
  // Spi means Sequential Positional Index which is equivalent to the input index in a
  // RexInput node
  std::vector<int> columnIdBySpi_;  // spi = 1,2,3,...

  // write mutex, only to be used inside catalog package
  std::shared_ptr<std::mutex> mutex_;

  TableDescriptor()
      : tableId(-1)
      , shard(-1)
      , nShards(0)
      , shardedColumnId(0)
      , sortedColumnId(0)
      , persistenceLevel(Data_Namespace::MemoryLevel::DISK_LEVEL)
      , hasDeletedCol(true)
      , mutex_(std::make_shared<std::mutex>()) {}
};

inline bool table_is_replicated(const TableDescriptor* td) {
  return td->partitions == "REPLICATED";
}

// compare for lowest id
inline bool compare_td_id(const TableDescriptor* first, const TableDescriptor* second) {
  return (first->tableId < second->tableId);
}

inline bool table_is_temporary(const TableDescriptor* td) {
  return td->persistenceLevel == Data_Namespace::MemoryLevel::CPU_LEVEL;
}

#endif  // TABLE_DESCRIPTOR