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 */

#ifndef FUNCTIONCOLUMN_H
#define FUNCTIONCOLUMN_H
#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();
    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);
    virtual ~FunctionColumn();

    /** 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 const std::string timeZone () const
    {
        return fTimeZone;
    }

    inline void timeZone (const std::string& timeZone)
    {
        fTimeZone = timeZone;
    }

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

    virtual const std::string toString() const;

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

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

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

    virtual void setSimpleColumnList();
    /**
     * 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
     */
    virtual bool singleTable(CalpontSystemCatalog::TableAliasName& tan);

private:
    /**
     * Fields
     */
    std::string fFunctionName;	/// function name
    std::string fTableAlias;	/// table alias which has the column
    std::string fData;			/// SQL representation
    std::string 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
     */
    virtual bool operator==(const TreeNode* t) const;

    /** @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
     */
    virtual bool operator!=(const TreeNode* 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 FunctionColumn& t) const;

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

        if (fResultType.scale == decimal.scale)
            return decimal;

        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 = fResultType.precision;
        return decimal;
    }
    virtual bool getBoolVal(rowgroup::Row& row, bool& isNull)
    {
        return fFunctor->getBoolVal(row, fFunctionParms, isNull, fOperationType);
    }
    virtual int32_t getDateIntVal(rowgroup::Row& row, bool& isNull)
    {
        return fFunctor->getDateIntVal(row, fFunctionParms, isNull, fOperationType);
    }
    virtual int64_t getDatetimeIntVal(rowgroup::Row& row, bool& isNull)
    {
        return fFunctor->getDatetimeIntVal(row, fFunctionParms, isNull, fOperationType);
    }
    virtual int64_t getTimestampIntVal(rowgroup::Row& row, bool& isNull)
    {
        return fFunctor->getTimestampIntVal(row, fFunctionParms, isNull, fOperationType);
    }
    virtual int64_t getTimeIntVal(rowgroup::Row& row, bool& isNull)
    {
        return fFunctor->getTimeIntVal(row, fFunctionParms, isNull, fOperationType);
    }

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

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

}
#endif //FUNCTIONCOLUMN_H