greenplumn IMDType 源码

greenplumn IMDType 代码

文件路径：/src/backend/gporca/libnaucrates/include/naucrates/md/IMDType.h

//---------------------------------------------------------------------------
//	Greenplum Database
//	Copyright (C) 2011 EMC Corp.
//
//	@filename:
//		IMDType.h
//
//	@doc:
//		Interface for types in the metadata cache
//---------------------------------------------------------------------------



#ifndef GPMD_IMDCacheType_H
#define GPMD_IMDCacheType_H

#include "gpos/base.h"

#include "naucrates/dxl/operators/CDXLDatum.h"
#include "naucrates/dxl/operators/CDXLScalarConstValue.h"
#include "naucrates/md/IMDCacheObject.h"

// fwd decl
namespace gpdxl
{
class CDXLScalarConstValue;
class CDXLDatum;
}  // namespace gpdxl

namespace gpnaucrates
{
class IDatum;
}

namespace gpmd
{
using namespace gpos;
using namespace gpnaucrates;
using namespace gpdxl;

//---------------------------------------------------------------------------
//	@class:
//		IMDType
//
//	@doc:
//		Interface for types in the metadata cache
//
//---------------------------------------------------------------------------
class IMDType : public IMDCacheObject
{
public:
	enum ETypeInfo
	{
		EtiInt2,
		EtiInt4,
		EtiInt8,
		EtiBool,
		EtiOid,
		EtiGeneric	// should be the last in this enum
	};

	// comparison type
	enum ECmpType
	{
		EcmptEq,   // equals
		EcmptNEq,  // not equals
		EcmptL,	   // less than
		EcmptLEq,  // less or equal to
		EcmptG,	   // greater than
		EcmptGEq,  // greater or equal to
		EcmptIDF,  // is distinct from
		EcmptOther
	};

	// aggregate type
	enum EAggType
	{
		EaggMin,
		EaggMax,
		EaggAvg,
		EaggSum,
		EaggCount,
		EaggGeneric
	};

	// object type
	Emdtype
	MDType() const override
	{
		return EmdtType;
	}

	virtual IMDId *GetDistrOpfamilyMdid() const = 0;

	// md id of cache object
	IMDId *MDId() const override = 0;

	// id of specified specified comparison operator type
	virtual IMDId *GetMdidForCmpType(ECmpType cmp_type) const = 0;

	// id of specified specified aggregate type
	virtual IMDId *GetMdidForAggType(EAggType agg_type) const = 0;

	// id of comparison operator for type used in btree lookups
	virtual const IMDId *CmpOpMdid() const = 0;

	// id of hash operator for type
	virtual BOOL IsHashable() const = 0;

	// type is merge joinable on '='
	virtual BOOL IsMergeJoinable() const = 0;

	// is type redistributable
	virtual BOOL IsRedistributable() const = 0;

	// id of the array type for the type
	virtual IMDId *GetArrayTypeMdid() const = 0;

	// type id
	virtual ETypeInfo GetDatumType() const = 0;

	// transformation function for datums
	virtual IDatum *GetDatumForDXLConstVal(
		const CDXLScalarConstValue *dxl_op) const = 0;

	// construct a datum from a DXL datum
	virtual IDatum *GetDatumForDXLDatum(CMemoryPool *mp,
										const CDXLDatum *dxl_datum) const = 0;

	// is type fixed length
	virtual BOOL IsFixedLength() const = 0;

	// is type composite
	virtual BOOL IsComposite() const = 0;

	virtual BOOL
	IsTextRelated() const
	{
		return false;
	}

	// id of the relation corresponding to a composite type
	virtual IMDId *GetBaseRelMdid() const = 0;

	// type length
	virtual ULONG Length() const = 0;

	// is type passed by value
	virtual BOOL IsPassedByValue() const = 0;

	// return the null constant for this type
	virtual IDatum *DatumNull() const = 0;

	// generate the DXL scalar constant from IDatum
	virtual CDXLScalarConstValue *GetDXLOpScConst(CMemoryPool *mp,
												  IDatum *datum) const = 0;

	// generate the DXL datum from IDatum
	virtual CDXLDatum *GetDatumVal(CMemoryPool *mp, IDatum *datum) const = 0;

	// generate the DXL datum representing null value
	virtual CDXLDatum *GetDXLDatumNull(CMemoryPool *mp) const = 0;

	// is type an ambiguous one? e.g., AnyElement in GPDB
	virtual BOOL
	IsAmbiguous() const
	{
		return false;
	}

	// string representation of comparison types
	static const CWStringConst *GetCmpTypeStr(IMDType::ECmpType cmp_type);

	// return true if we can perform statistical comparison between datums of these two types; else return false
	static BOOL StatsAreComparable(const IMDType *mdtype_first,
								   const IMDType *mdtype_second);

	// return true if we can perform statistical comparison between datum of the given type and a given datum; else return false
	static BOOL StatsAreComparable(const IMDType *mdtype_first,
								   const IDatum *datum_second);
};
}  // namespace gpmd

#endif	// !GPMD_IMDCacheType_H

// EOF

相关信息

greenplumn 源码目录

相关文章

greenplumn CDXLBucket 源码

greenplumn CDXLColStats 源码

greenplumn CDXLRelStats 源码

greenplumn CDXLStatsDerivedColumn 源码

greenplumn CDXLStatsDerivedRelation 源码

greenplumn CGPDBTypeHelper 源码

greenplumn CMDAggregateGPDB 源码

greenplumn CMDArrayCoerceCastGPDB 源码

greenplumn CMDCastGPDB 源码

greenplumn CMDCheckConstraintGPDB 源码