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

/* Copyright (C) 2014 InfiniDB, Inc.

   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_ntile.cpp 3932 2013-06-25 16:08:10Z xlou $

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

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

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

#include "idborderby.h"
using namespace ordering;

#include "joblisttypes.h"
#include "calpontsystemcatalog.h"
#include "constantcolumn.h"
using namespace execplan;

#include "windowfunctionstep.h"
using namespace joblist;

#include "wf_ntile.h"

namespace windowfunction
{
boost::shared_ptr<WindowFunctionType> WF_ntile::makeFunction(int id, const string& name, int,
                                                             WindowFunctionColumn*)
{
  boost::shared_ptr<WindowFunctionType> func(new WF_ntile(id, name));
  return func;
}

WindowFunctionType* WF_ntile::clone() const
{
  return new WF_ntile(*this);
}

void WF_ntile::resetData()
{
  WindowFunctionType::resetData();
}

void WF_ntile::parseParms(const std::vector<execplan::SRCP>& parms)
{
  // parms[0]: nt
  auto* cc = dynamic_cast<ConstantColumn*>(parms[0].get());

  if (cc != nullptr)
  {
    fNtileNull = false;
    fNtile = cc->getIntVal(fRow, fNtileNull);  // row not used, no need to setData.

    if (!fNtileNull && fNtile <= 0)
    {
      ostringstream oss;
      oss << fNtile;
      throw IDBExcept(IDBErrorInfo::instance()->errorMsg(ERR_WF_ARG_OUT_OF_RANGE, oss.str()),
                      ERR_WF_ARG_OUT_OF_RANGE);
    }
  }
}

void WF_ntile::operator()(int64_t b, int64_t e, int64_t c)
{
  int64_t idx = fFieldIndex[1];

  if (idx != -1)
  {
    fRow.setData(getPointer(fRowData->at(b)));

    if (idx != -1)
    {
      double tmp = 1.0;
      fNtileNull = fRow.isNullValue(idx);

      if (!fNtileNull)
        implicit2T(idx, tmp, 0);

      if (!fNtileNull && tmp <= 0)
      {
        ostringstream oss;
        oss << tmp;
        throw IDBExcept(IDBErrorInfo::instance()->errorMsg(ERR_WF_ARG_OUT_OF_RANGE, oss.str()),
                        ERR_WF_ARG_OUT_OF_RANGE);
      }

      fNtile = round(tmp);
    }
  }

  c = b;

  if (!fNtileNull)
  {
    int64_t rowPerBucket = (e - b + 1) / fNtile;
    int64_t n = rowPerBucket * fNtile;
    int64_t x = (e - b + 1) - n;  // extra
    int64_t y = 0;
    int64_t z = 0;

    while (c <= e)
    {
      if (c % 1000 == 0 && fStep->cancelled())
        break;

      y = rowPerBucket + ((x-- > 0) ? 1 : 0);
      z++;

      for (int64_t i = 0; i < y && c <= e; i++)
      {
        fRow.setData(getPointer(fRowData->at(c++)));
        setIntValue(fFieldIndex[0], z);
      }
    }
  }
  else
  {
    while (c <= e)
    {
      if (c % 1000 == 0 && fStep->cancelled())
        break;

      fRow.setData(getPointer(fRowData->at(c++)));
      setIntValue(fFieldIndex[0], joblist::BIGINTNULL);
    }
  }
}

}  // namespace windowfunction