dbcon/execplan/constantfilter.h

/* 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: constantfilter.h 9210 2013-01-21 14:10:42Z rdempsey $
*
*
***********************************************************************/
/** @file */

#ifndef CONSTANTFILTER_H
#define CONSTANTFILTER_H
#include <string>
#include <iosfwd>
#include <vector>

#include "filter.h"
#include "simplefilter.h"
#include "simplecolumn.h"
#include "operator.h"

/**
 * Namespace
 */
namespace execplan
{

class ReturnedColumn;
class AggregateColumn;
class WindowFunctionColumn;

/**
 * @brief A class to represent a simple column op constant predicate
 *
 * This class is a specialization of class Filter that handles one or
 * more simple filters, where one side of operand is a constant. It
 * contains a list of simple filters and every simplefilter has the
 * same column. All the simple filters are connected by the same
 * operator (either "and" or "or"). This class is introduced for
 * easy operation combine for primitive processor.
 */
class ConstantFilter : public Filter
{

public:
    /**
     * Types and constants
     */
    typedef std::vector<SSFP> FilterList;

    /**
     * Constructors
     */
    ConstantFilter();
    ConstantFilter(const SOP& op, ReturnedColumn* lhs, ReturnedColumn* rhs);
    ConstantFilter(SimpleFilter* sf);

    //not needed yet
    //ConstantFilter(const ConstantFilter& rhs);

    /**
     * Destructors
     */
    virtual ~ConstantFilter();

    /**
     * Accessor Methods
     */
    const FilterList& filterList() const
    {
        return fFilterList;
    }
    void filterList( const FilterList& filterList)
    {
        fFilterList = filterList;
    }
    const SOP& op() const
    {
        return fOp;
    }
    void op(const SOP& op)
    {
        fOp = op;
    }
    const SRCP& col() const
    {
        return fCol;
    }
    void col(const SRCP& col)
    {
        fCol = col;
    }

    /**
     * Operations
     */
    void pushFilter (SimpleFilter* sf)
    {
        SSFP ssfp(sf);
        fFilterList.push_back(ssfp);
    }

    //virtual const std::string data() const;
    virtual const std::string toString() const;

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

    /** @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 ConstantFilter& 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 ConstantFilter& t) const;

    /** @brief test if this filter can be combined with the argument filter
      *  This is for operation combine optimization
      *  @param f the filter that this fiter tries to combine with
      *  @param op the operator that connects the two filters. if one or both of the
      *  two filters is constantFilter, need to make sure operator is consistant.
      *  @return a filter(constantfilter) if successfully combined. otherwise
      *     	 return NULL
      */
    // Used by Oracle frontend, deprecated now.
    //virtual Filter* combinable(Filter* f, Operator* op);

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

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

    void setDerivedTable();
    virtual void replaceRealCol(std::vector<SRCP>&);
    virtual bool hasAggregate();

private:
    SOP fOp;       /// connect operator (and or)
    FilterList fFilterList; /// vector of simple filters
    SRCP fCol;     /// the common column
    std::string fFunctionName;  /// function name

    /***********************************************************
     *                  F&E framework                          *
     ***********************************************************/
public:
    ConstantFilter(const ConstantFilter& rhs);
    inline virtual ConstantFilter* clone() const
    {
        return new ConstantFilter (*this);
    }

    inline virtual bool getBoolVal(rowgroup::Row& row, bool& isNull);

    // get all simple columns involved in this column
    const std::vector<SimpleColumn*>& simpleColumnList();
    // walk through the constant filter operands to re-populate fSimpleColumnList
    void setSimpleColumnList();

    // get all aggregate columns involved in this column
    const std::vector<AggregateColumn*>& aggColumnList() const
    {
        return fAggColumnList;
    }

private:
    std::vector<SimpleColumn*> fSimpleColumnList;
    std::vector<AggregateColumn*> fAggColumnList;
    std::vector<WindowFunctionColumn*> fWindowFunctionColumnList;
};

inline bool ConstantFilter::getBoolVal(rowgroup::Row& row, bool& isNull)
{
    switch (fOp->op())
    {
        case OP_AND:
            for (uint32_t i = 0; i < fFilterList.size(); i++)
                if (!fFilterList[i]->getBoolVal(row, isNull))
                    return false;

            return true;

        case OP_OR:
            for (uint32_t i = 0; i < fFilterList.size(); i++)
                if (fFilterList[i]->getBoolVal(row, isNull))
                    return true;

            return false;

        default:
        {
            std::ostringstream oss;
            oss << "ConstantFilter:: Non support logic operation: " << fOp->op();
            throw logging::InvalidOperationExcept(oss.str());
        }
    }
}

std::ostream& operator<<(std::ostream& output, const ConstantFilter& rhs);

}
#endif //CONSTANTFILTER_H