mariadb-columnstore-engine/dbcon/execplan/functioncolumn.h

/* 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: functioncolumn.h 9679 2013-07-11 22:32:03Z zzhu $
 *
 *
 ***********************************************************************/
/** @file */

#pragma once
#include <string>
#include <iosfwd>
#include <vector>

#include "returnedcolumn.h"
#include "functor.h"

namespace messageqcpp
{
class ByteStream;
}

/**
 * Namespace
 */
namespace execplan
{
/**
 * @brief A class to represent a functional column
 *
 * This class is a specialization of class ReturnedColumn that
 * handles a functional column like "extract(...)" and "substr(...)"
 */
class FunctionColumn : public ReturnedColumn
{
 public:
  FunctionColumn();
  explicit FunctionColumn(std::string& funcName);
  FunctionColumn(const std::string& functionName, const std::string& funcParmsInString,
                 const uint32_t sessionID = 0);
  FunctionColumn(const FunctionColumn& rhs, const uint32_t sessionID = 0);
  ~FunctionColumn() override;

  /** get function name
   *
   * get the function name for this function column
   */
  inline const std::string& functionName() const
  {
    return fFunctionName;
  }

  /** set function name
   *
   * set the function name for this function column
   */
  inline void functionName(const std::string functionName)
  {
    fFunctionName = functionName;
  }

  /** get function parameters
   *
   * get the function parameters for this function column.
   * @return a vector of paramenters in string format
   */
  inline const funcexp::FunctionParm& functionParms() const
  {
    return fFunctionParms;
  }

  /** set function parameters
   *
   * set the function parameters for this function column.
   */
  void functionParms(const funcexp::FunctionParm& functionParms)
  {
    fFunctionParms = functionParms;
  }

  /** set function parameters
   *
   * set the function parameters for this function column.
   * pass in the functionParms with parenthesis as one string.
   * tokenize the string with ' ' or ',' and form a vector of
   * parameters in string.
   */
  void funcParms(const std::string& funcParmsInString);

  /** get table alias name
   *
   * get the table alias name for this function
   */
  inline const std::string& tableAlias() const
  {
    return fTableAlias;
  }

  /** set table alias name
   *
   * set the table alias name for this function
   */
  inline void tableAlias(const std::string& tableAlias)
  {
    fTableAlias = tableAlias;
  }

  inline long timeZone() const
  {
    return fTimeZone;
  }

  inline void timeZone(const long timeZone)
  {
    fTimeZone = timeZone;
  }

  const std::string data() const override;
  void data(const std::string data) override
  {
    fData = data;
  }

  const std::string toString() const override;

  /** return a copy of this pointer
   *
   * deep copy of this pointer and return the copy
   */
  inline FunctionColumn* clone() const override
  {
    return new FunctionColumn(*this);
  }

  /**
   * The serialization interface
   */
  void serialize(messageqcpp::ByteStream&) const override;
  void unserialize(messageqcpp::ByteStream&) override;

  using ReturnedColumn::hasAggregate;
  bool hasAggregate() override;
  bool hasWindowFunc() override;
  void setDerivedTable() override;
  void replaceRealCol(std::vector<SRCP>&) override;
  virtual const std::vector<SimpleColumn*>& simpleColumnList() const override
  {
    return fSimpleColumnList;
  }

  void setSimpleColumnList() override;
  /**
   * Return the tableAlias name of the table that the column arguments belong to.
   *
   * @param TableAliasName that will be set in the function
   * @return true, if all arguments belong to one table
   *         false, if multiple tables are involved in the function
   */
  std::optional<CalpontSystemCatalog::TableAliasName> singleTable() override;

  std::string toCppCode(IncludeSet& includes) const override;

 private:
  /**
   * Fields
   */
  std::string fFunctionName;  /// function name
  std::string fTableAlias;    /// table alias which has the column
  std::string fData;          /// SQL representation
  long fTimeZone;

  /** @brief Do a deep, strict (as opposed to semantic) equivalence test
   *
   * Do a deep, strict (as opposed to semantic) equivalence test.
   * @return true iff every member of t is a duplicate copy of every member of this; false otherwise
   */
  bool operator==(const TreeNode* t) const override;

  /** @brief Do a deep, strict (as opposed to semantic) equivalence test
   *
   * Do a deep, strict (as opposed to semantic) equivalence test.
   * @return true iff every member of t is a duplicate copy of every member of this; false otherwise
   */
  bool operator==(const FunctionColumn& t) const;

  /** @brief Do a deep, strict (as opposed to semantic) equivalence test
   *
   * Do a deep, strict (as opposed to semantic) equivalence test.
   * @return false iff every member of t is a duplicate copy of every member of this; true otherwise
   */
  bool operator!=(const TreeNode* t) const override;

  /** @brief Do a deep, strict (as opposed to semantic) equivalence test
   *
   * Do a deep, strict (as opposed to semantic) equivalence test.
   * @return false iff every member of t is a duplicate copy of every member of this; true otherwise
   */
  bool operator!=(const FunctionColumn& t) const;

  /***********************************************************
   *				  F&E framework						  *
   ***********************************************************/
 public:
  const utils::NullString& getStrVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    fResult.strVal.dropString();
    std::string val = fFunctor->getStrVal(row, fFunctionParms, isNull, fOperationType);
    if (!isNull)
    {
      fResult.strVal.assign(val);
    }
    return fResult.strVal;
  }
  int64_t getIntVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    return fFunctor->getIntVal(row, fFunctionParms, isNull, fOperationType);
  }
  uint64_t getUintVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    return fFunctor->getUintVal(row, fFunctionParms, isNull, fOperationType);
  }
  float getFloatVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    return fFunctor->getFloatVal(row, fFunctionParms, isNull, fOperationType);
  }
  double getDoubleVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    return fFunctor->getDoubleVal(row, fFunctionParms, isNull, fOperationType);
  }
  long double getLongDoubleVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    return fFunctor->getLongDoubleVal(row, fFunctionParms, isNull, fOperationType);
  }
  IDB_Decimal getDecimalVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    IDB_Decimal decimal = fFunctor->getDecimalVal(row, fFunctionParms, isNull, fOperationType);

    if (UNLIKELY(fResultType.colWidth == utils::MAXLEGACYWIDTH && fResultType.scale == decimal.scale))
      return decimal;

    if (LIKELY(fResultType.isWideDecimalType()))
    {
      decimal.s128Value = (datatypes::Decimal::isWideDecimalTypeByPrecision(decimal.precision))
                              ? decimal.s128Value
                              : decimal.value;

      int128_t scaleMultiplier;
      int32_t scaleDiff = fResultType.scale - decimal.scale;
      datatypes::getScaleDivisor(scaleMultiplier, abs(scaleDiff));

      if (scaleMultiplier > 1)
      {
        if (scaleDiff > 0)
        {
          // TODO MCOL-641 Unconditional overflow check
          datatypes::MultiplicationNoOverflowCheck mul;
          mul(decimal.s128Value, scaleMultiplier, decimal.s128Value);
        }
        else
        {
          decimal = decimal.integralWideRound();
        }
      }
    }
    else if (fResultType.colWidth == utils::MAXLEGACYWIDTH)
    {
      if (fResultType.scale > decimal.scale)
        decimal.value *= IDB_pow[fResultType.scale - decimal.scale];
      else
        decimal.value =
            (int64_t)(decimal.value > 0
                          ? (double)decimal.value / IDB_pow[decimal.scale - fResultType.scale] + 0.5
                          : (double)decimal.value / IDB_pow[decimal.scale - fResultType.scale] - 0.5);
    }

    decimal.scale = fResultType.scale;
    decimal.precision = std::max(fResultType.precision, static_cast<int32_t>(decimal.precision));
    return decimal;
  }
  bool getBoolVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    return fFunctor->getBoolVal(row, fFunctionParms, isNull, fOperationType);
  }
  int32_t getDateIntVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    return fFunctor->getDateIntVal(row, fFunctionParms, isNull, fOperationType);
  }
  int64_t getDatetimeIntVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    return fFunctor->getDatetimeIntVal(row, fFunctionParms, isNull, fOperationType);
  }
  int64_t getTimestampIntVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    return fFunctor->getTimestampIntVal(row, fFunctionParms, isNull, fOperationType);
  }
  int64_t getTimeIntVal(rowgroup::Row& row, bool& isNull) override
  {
    fOperationType.setTimeZone(fTimeZone);
    return fFunctor->getTimeIntVal(row, fFunctionParms, isNull, fOperationType);
  }

  void setFunctor(funcexp::Func* functor)
  {
    fFunctor = functor;
  }

 private:
  funcexp::FunctionParm fFunctionParms;
  funcexp::Func* fFunctor;                   /// functor to execute this function
  funcexp::Func* fDynamicFunctor = nullptr;  // for rand encode decode
};

/**
 * ostream operator
 */
std::ostream& operator<<(std::ostream& output, const FunctionColumn& rhs);

}  // namespace execplan