greenplumn COrderSpec 代码
文件路径：/src/backend/gporca/libgpopt/include/gpopt/base/COrderSpec.h
/---------------------------------------------------------------------------
/ Greenplum Database
/ Copyright (C) 2011 EMC Corp.
/
/ @filename:
/ COrderSpec.h
/
/ @doc:
/ Description of sort order;
/ Can be used as required or derived property;
/---------------------------------------------------------------------------
#ifndef GPOPT_COrderSpec_H
#define GPOPT_COrderSpec_H
#include "gpos/base.h"
#include "gpos/common/DbgPrintMixin.h"
#include "gpopt/base/CColRef.h"
#include "gpopt/base/CPropSpec.h"
#include "naucrates/md/IMDId.h"
namespace gpopt
{
/ type definition of corresponding dynamic pointer array
class COrderSpec;
using COrderSpecArray = CDynamicPtrArray<COrderSpec, CleanupRelease>;
using namespace gpos;
/ fwd declaration
class CColRefSet;
/---------------------------------------------------------------------------
/ @class:
/ COrderSpec
/
/ @doc:
/ Array of Order Expressions
/
/---------------------------------------------------------------------------
class COrderSpec : public CPropSpec
{
public:
enum ENullTreatment
{
EntAuto, / default behavior, as implemented by operator
EntFirst,
EntLast,
EntSentinel
};
private:
/---------------------------------------------------------------------------
/ @class:
/ COrderExpression
/
/ @doc:
/ Spec of sort order component consisting of
/
/ 1. sort operator's mdid
/ 2. column reference
/ 3. definition of NULL treatment
/
/---------------------------------------------------------------------------
class COrderExpression : public gpos::DbgPrintMixin<COrderExpression>
{
private:
/ MD id of sort operator
gpmd::IMDId *m_mdid;
/ sort column
const CColRef *m_pcr;
/ null treatment
ENullTreatment m_ent;
public:
COrderExpression(const COrderExpression &) = delete;
/ ctor
COrderExpression(gpmd::IMDId *mdid, const CColRef *colref,
ENullTreatment ent);
/ dtor
virtual ~COrderExpression();
/ accessor of sort operator midid
gpmd::IMDId *
GetMdIdSortOp() const
{
return m_mdid;
}
/ accessor of sort column
const CColRef *
Pcr() const
{
return m_pcr;
}
/ accessor of null treatment
ENullTreatment
Ent() const
{
return m_ent;
}
/ check if order specs match
BOOL Matches(const COrderExpression *poe) const;
/ print
IOstream &OsPrint(IOstream &os) const;
}; / class COrderExpression
/ array of order expressions
using COrderExpressionArray =
CDynamicPtrArray<COrderExpression, CleanupDelete>;
/ memory pool
CMemoryPool *m_mp;
/ components of order spec
COrderExpressionArray *m_pdrgpoe;
/ extract columns from order spec into the given column set
void ExtractCols(CColRefSet *pcrs) const;
public:
COrderSpec(const COrderSpec &) = delete;
/ ctor
explicit COrderSpec(CMemoryPool *mp);
/ dtor
~COrderSpec() override;
/ number of sort expressions
ULONG
UlSortColumns() const
{
return m_pdrgpoe->Size();
}
/ accessor of sort operator of the n-th component
IMDId *
GetMdIdSortOp(ULONG ul) const
{
COrderExpression *poe = (*m_pdrgpoe)[ul];
return poe->GetMdIdSortOp();
}
/ accessor of sort column of the n-th component
const CColRef *
Pcr(ULONG ul) const
{
COrderExpression *poe = (*m_pdrgpoe)[ul];
return poe->Pcr();
}
/ accessor of null treatment of the n-th component
ENullTreatment
Ent(ULONG ul) const
{
COrderExpression *poe = (*m_pdrgpoe)[ul];
return poe->Ent();
}
/ check if order spec has no columns
BOOL
IsEmpty() const
{
return UlSortColumns() == 0;
}
/ append new component
void Append(gpmd::IMDId *mdid, const CColRef *colref, ENullTreatment ent);
/ extract colref set of order columns
CColRefSet *PcrsUsed(CMemoryPool *mp) const override;
/ property type
EPropSpecType
Epst() const override
{
return EpstOrder;
}
/ check if order specs match
BOOL Matches(const COrderSpec *pos) const;
/ check if order specs satisfies req'd spec
BOOL FSatisfies(const COrderSpec *pos) const;
/ append enforcers to dynamic array for the given plan properties
void AppendEnforcers(CMemoryPool *mp, CExpressionHandle &exprhdl,
CReqdPropPlan *prpp, CExpressionArray *pdrgpexpr,
CExpression *pexpr) override;
/ hash function
ULONG HashValue() const override;
/ return a copy of the order spec with remapped columns
virtual COrderSpec *PosCopyWithRemappedColumns(
CMemoryPool *mp, UlongToColRefMap *colref_mapping, BOOL must_exist);
/ return a copy of the order spec after excluding the given columns
virtual COrderSpec *PosExcludeColumns(CMemoryPool *mp, CColRefSet *pcrs);
/ print
IOstream &OsPrint(IOstream &os) const override;
/ matching function over order spec arrays
static BOOL Equals(const COrderSpecArray *pdrgposFirst,
const COrderSpecArray *pdrgposSecond);
/ combine hash values of a maximum number of entries
static ULONG HashValue(const COrderSpecArray *pdrgpos, ULONG ulMaxSize);
/ print array of order spec objects
static IOstream &OsPrint(IOstream &os, const COrderSpecArray *pdrgpos);
/ extract colref set of order columns used by elements of order spec array
static CColRefSet *GetColRefSet(CMemoryPool *mp, COrderSpecArray *pdrgpos);
/ filter out array of order specs from order expressions using the passed columns
static COrderSpecArray *PdrgposExclude(CMemoryPool *mp,
COrderSpecArray *pdrgpos,
CColRefSet *pcrsToExclude);
}; / class COrderSpec
} / namespace gpopt
#endif / !GPOPT_COrderSpec_H
/ EOF
相关信息
相关文章
greenplumn CColConstraintsArrayMapper 源码