mariadb-columnstore-engine/utils/windowfunction/wf_min_max.cpp

/* Copyright (C) 2014 InfiniDB, Inc.
   Copyright (c) 2019 MariaDB Corporation

   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 Street, Fifth Floor, Boston,
   MA 02110-1301, USA. */

//  $Id: wf_min_max.cpp 3932 2013-06-25 16:08:10Z xlou $

// #define NDEBUG
#include <cmath>
using namespace std;

#include <boost/shared_ptr.hpp>
using namespace boost;

#include "loggingid.h"
#include "errorcodes.h"
using namespace logging;

#include "calpontsystemcatalog.h"
using namespace execplan;

#include "windowfunctionstep.h"
using namespace joblist;

#include "wf_min_max.h"

namespace windowfunction
{
template <typename T>
boost::shared_ptr<WindowFunctionType> WF_min_max<T>::makeFunction(int id, const string& name, int ct,
                                                                  WindowFunctionColumn* wc)
{
  boost::shared_ptr<WindowFunctionType> func;

  switch (ct)
  {
    case CalpontSystemCatalog::TINYINT:
    case CalpontSystemCatalog::SMALLINT:
    case CalpontSystemCatalog::MEDINT:
    case CalpontSystemCatalog::INT:
    case CalpontSystemCatalog::BIGINT:
    {
      func.reset(new WF_min_max<int64_t>(id, name));
      break;
    }

    case CalpontSystemCatalog::UTINYINT:
    case CalpontSystemCatalog::USMALLINT:
    case CalpontSystemCatalog::UMEDINT:
    case CalpontSystemCatalog::UINT:
    case CalpontSystemCatalog::UBIGINT:
    case CalpontSystemCatalog::DATE:
    case CalpontSystemCatalog::DATETIME:
    case CalpontSystemCatalog::TIMESTAMP:
    case CalpontSystemCatalog::TIME:
    {
      func.reset(new WF_min_max<uint64_t>(id, name));
      break;
    }

    case CalpontSystemCatalog::DECIMAL:
    case CalpontSystemCatalog::UDECIMAL:
    {
      decltype(datatypes::MAXDECIMALWIDTH) width = wc->functionParms()[0]->resultType().colWidth;

      if (width < datatypes::MAXDECIMALWIDTH)
      {
        if (ct == CalpontSystemCatalog::UDECIMAL)
          func.reset(new WF_min_max<uint64_t>(id, name));
        else
          func.reset(new WF_min_max<int64_t>(id, name));
      }
      else
      {
        func.reset(new WF_min_max<int128_t>(id, name));
      }
      break;
    }

    case CalpontSystemCatalog::DOUBLE:
    case CalpontSystemCatalog::UDOUBLE:
    {
      func.reset(new WF_min_max<double>(id, name));
      break;
    }

    case CalpontSystemCatalog::FLOAT:
    case CalpontSystemCatalog::UFLOAT:
    {
      func.reset(new WF_min_max<float>(id, name));
      break;
    }

    case CalpontSystemCatalog::LONGDOUBLE:
    {
      func.reset(new WF_min_max<long double>(id, name));
      break;
    }

    default:
    {
      func.reset(new WF_min_max<utils::NullString>(id, name));
      break;
    }
  }

  return func;
}

template <typename T>
WindowFunctionType* WF_min_max<T>::clone() const
{
  return new WF_min_max<T>(*this);
}

template <typename T>
void WF_min_max<T>::resetData()
{
  fCount = 0;

  WindowFunctionType::resetData();
}

template <typename T>
void WF_min_max<T>::operator()(int64_t b, int64_t e, int64_t c)
{
  // for unbounded - current row special handling
  if (fPrev >= b && fPrev < c)
    b = c;
  else if (fPrev <= e && fPrev > c)
    e = c;

  uint64_t colIn = fFieldIndex[1];

  for (int64_t i = b; i <= e; i++)
  {
    if (i % 1000 == 0 && fStep->cancelled())
      break;

    fRow.setData(getPointer(fRowData->at(i)));

    if (fRow.isNullValue(colIn) == true)
      continue;

    T valIn;
    getValue(colIn, valIn);

    if ((fCount == 0) || (valIn < fValue && fFunctionId == WF__MIN) ||
        (valIn > fValue && fFunctionId == WF__MAX))
    {
      fValue = valIn;
    }

    fCount++;
  }

  T* v = ((fCount > 0) ? &fValue : NULL);
  setValue(fRow.getColType(fFieldIndex[0]), b, e, c, v);

  fPrev = c;
}

template boost::shared_ptr<WindowFunctionType> WF_min_max<int64_t>::makeFunction(int, const string&, int,
                                                                                 WindowFunctionColumn*);

}  // namespace windowfunction