greenplumn CDXLDatumGeneric 代码
文件路径：/src/backend/gporca/libnaucrates/include/naucrates/dxl/operators/CDXLDatumGeneric.h
/---------------------------------------------------------------------------
/ Greenplum Database
/ Copyright (C) 2012 EMC Corp.
/
/ @filename:
/ CDXLDatumGeneric.h
/
/ @doc:
/ Class for representing DXL datum of type generic
/
/ @owner:
/
/
/ @test:
/
/---------------------------------------------------------------------------
#ifndef GPDXL_CDXLDatumGeneric_H
#define GPDXL_CDXLDatumGeneric_H
#include "gpos/base.h"
#include "gpos/common/CDouble.h"
#include "naucrates/dxl/operators/CDXLDatum.h"
namespace gpdxl
{
using namespace gpos;
/ fwd decl
class CXMLSerializer;
/---------------------------------------------------------------------------
/ @class:
/ CDXLDatumGeneric
/
/ @doc:
/ Class for representing DXL datum of type generic
/
/---------------------------------------------------------------------------
class CDXLDatumGeneric : public CDXLDatum
{
private:
protected:
/ datum byte array
BYTE *m_byte_array;
public:
CDXLDatumGeneric(const CDXLDatumGeneric &) = delete;
/ ctor
CDXLDatumGeneric(CMemoryPool *mp, IMDId *mdid_type, INT type_modifier,
BOOL is_null, BYTE *data, ULONG length);
/ dtor
~CDXLDatumGeneric() override;
/ byte array
const BYTE *GetByteArray() const;
/ serialize the datum as the given element
void Serialize(CXMLSerializer *xml_serializer) override;
/ datum type
EdxldatumType
GetDatumType() const override
{
return CDXLDatum::EdxldatumGeneric;
}
/ conversion function
static CDXLDatumGeneric *
Cast(CDXLDatum *dxl_datum)
{
GPOS_ASSERT(nullptr != dxl_datum);
GPOS_ASSERT(CDXLDatum::EdxldatumGeneric == dxl_datum->GetDatumType() ||
CDXLDatum::EdxldatumStatsDoubleMappable ==
dxl_datum->GetDatumType() ||
CDXLDatum::EdxldatumStatsLintMappable ==
dxl_datum->GetDatumType());
return dynamic_cast<CDXLDatumGeneric *>(dxl_datum);
}
/ statistics related APIs
/ can datum be mapped to LINT
virtual BOOL
IsDatumMappableToLINT() const
{
return false;
}
/ return the lint mapping needed for statistics computation
virtual LINT
GetLINTMapping() const
{
GPOS_ASSERT(IsDatumMappableToLINT());
return 0;
}
/ can datum be mapped to a double
virtual BOOL
IsDatumMappableToDouble() const
{
return false;
}
/ return the double mapping needed for statistics computation
virtual CDouble
GetDoubleMapping() const
{
GPOS_ASSERT(IsDatumMappableToDouble());
return 0;
}
};
} / namespace gpdxl
#endif / !GPDXL_CDXLDatumGeneric_H
/ EOF