greenplumn CLogicalSequence 源码

greenplumn CLogicalSequence 代码

文件路径：/src/backend/gporca/libgpopt/include/gpopt/operators/CLogicalSequence.h

//---------------------------------------------------------------------------
//	Greenplum Database
//	Copyright (C) 2012 EMC Corp.
//
//	@filename:
//		CLogicalSequence.h
//
//	@doc:
//		Logical sequence operator
//---------------------------------------------------------------------------
#ifndef GPOPT_CLogicalSequence_H
#define GPOPT_CLogicalSequence_H

#include "gpos/base.h"

#include "gpopt/operators/CExpressionHandle.h"
#include "gpopt/operators/CLogical.h"

namespace gpopt
{
//---------------------------------------------------------------------------
//	@class:
//		CLogicalSequence
//
//	@doc:
//		Logical sequence operator
//
//---------------------------------------------------------------------------
class CLogicalSequence : public CLogical
{
private:
public:
	CLogicalSequence(const CLogicalSequence &) = delete;

	// ctor
	explicit CLogicalSequence(CMemoryPool *mp);

	// dtor
	~CLogicalSequence() override = default;

	// ident accessors
	EOperatorId
	Eopid() const override
	{
		return EopLogicalSequence;
	}

	// return a string for operator name
	const CHAR *
	SzId() const override
	{
		return "CLogicalSequence";
	}

	// match function
	BOOL Matches(COperator *pop) const override;


	// sensitivity to order of inputs
	BOOL
	FInputOrderSensitive() const override
	{
		return true;
	}

	// return a copy of the operator with remapped columns
	COperator *
	PopCopyWithRemappedColumns(CMemoryPool *,		//mp,
							   UlongToColRefMap *,	//colref_mapping,
							   BOOL					//must_exist
							   ) override
	{
		return PopCopyDefault();
	}

	//-------------------------------------------------------------------------------------
	// Derived Relational Properties
	//-------------------------------------------------------------------------------------

	// derive output columns
	CColRefSet *DeriveOutputColumns(CMemoryPool *mp,
									CExpressionHandle &exprhdl) override;

	// dervive keys
	CKeyCollection *DeriveKeyCollection(
		CMemoryPool *mp, CExpressionHandle &exprhdl) const override;

	// derive max card
	CMaxCard DeriveMaxCard(CMemoryPool *mp,
						   CExpressionHandle &exprhdl) const override;

	// derive partition consumer info
	CPartInfo *DerivePartitionInfo(CMemoryPool *mp,
								   CExpressionHandle &exprhdl) const override;

	// derive constraint property
	CPropConstraint *
	DerivePropertyConstraint(CMemoryPool *,	 //mp,
							 CExpressionHandle &exprhdl) const override
	{
		return PpcDeriveConstraintPassThru(exprhdl, exprhdl.Arity() - 1);
	}

	//-------------------------------------------------------------------------------------
	// Required Relational Properties
	//-------------------------------------------------------------------------------------

	// compute required stat columns of the n-th child
	CColRefSet *
	PcrsStat(CMemoryPool *mp, CExpressionHandle &exprhdl, CColRefSet *pcrsInput,
			 ULONG child_index) const override
	{
		const ULONG ulLastChildIndex = exprhdl.Arity() - 1;
		if (child_index == ulLastChildIndex)
		{
			// only pass through the required stats column to the last child since
			// the output of the sequence operator is the output of the last child
			return PcrsStatsPassThru(pcrsInput);
		}

		return GPOS_NEW(mp) CColRefSet(mp);
	}

	// derive statistics
	IStatistics *
	PstatsDerive(CMemoryPool *,	 //mp,
				 CExpressionHandle &exprhdl,
				 IStatisticsArray *	 //stats_ctxt
	) const override
	{
		// pass through stats from last child
		IStatistics *stats = exprhdl.Pstats(exprhdl.Arity() - 1);
		stats->AddRef();

		return stats;
	}

	//-------------------------------------------------------------------------------------
	// Transformations
	//-------------------------------------------------------------------------------------

	// candidate set of xforms
	CXformSet *PxfsCandidates(CMemoryPool *mp) const override;

	// stat promise
	EStatPromise
	Esp(CExpressionHandle &) const override
	{
		return CLogical::EspHigh;
	}

	//-------------------------------------------------------------------------------------
	//-------------------------------------------------------------------------------------
	//-------------------------------------------------------------------------------------

	// conversion function
	static CLogicalSequence *
	PopConvert(COperator *pop)
	{
		GPOS_ASSERT(nullptr != pop);
		GPOS_ASSERT(EopLogicalSequence == pop->Eopid());

		return dynamic_cast<CLogicalSequence *>(pop);
	}

};	// class CLogicalSequence

}  // namespace gpopt


#endif	// !GPOPT_CLogicalSequence_H

// EOF

相关信息

greenplumn 源码目录

相关文章

greenplumn CExpression 源码

greenplumn CExpressionFactorizer 源码

greenplumn CExpressionHandle 源码

greenplumn CExpressionPreprocessor 源码

greenplumn CExpressionUtils 源码

greenplumn CHashedDistributions 源码

greenplumn CLogical 源码

greenplumn CLogicalApply 源码

greenplumn CLogicalAssert 源码

greenplumn CLogicalBitmapTableGet 源码