C++ DrgPpartkeys类代码示例

//---------------------------------------------------------------------------
//	@function:
//		CPartInfo::CPartInfoEntry::PpartinfoentryAddRemappedKeys
//
//	@doc:
//		Create a copy of the current object, and add a set of remapped
//		part keys to this entry, using the existing keys and the given hashmap
//
//---------------------------------------------------------------------------
CPartInfo::CPartInfoEntry *
CPartInfo::CPartInfoEntry::PpartinfoentryAddRemappedKeys
	(
	IMemoryPool *pmp,
	CColRefSet *pcrs,
	HMUlCr *phmulcr
	)
{
	GPOS_ASSERT(NULL != pcrs);
	GPOS_ASSERT(NULL != phmulcr);

    DrgPpartkeys *pdrgppartkeys = CPartKeys::PdrgppartkeysCopy(pmp, m_pdrgppartkeys);

	const ULONG ulSize = m_pdrgppartkeys->UlLength();
	for (ULONG ul = 0; ul < ulSize; ul++)
	{
		CPartKeys *ppartkeys = (*m_pdrgppartkeys)[ul];

		if (ppartkeys->FOverlap(pcrs))
		{
			pdrgppartkeys->Append(ppartkeys->PpartkeysRemap(pmp, phmulcr));
			break;
		}
	}

	m_pmdid->AddRef();
	CPartConstraint *ppartcnstrRel = m_ppartcnstrRel->PpartcnstrCopyWithRemappedColumns(pmp, phmulcr, false /*fMustExist*/);

	return GPOS_NEW(pmp) CPartInfoEntry(m_ulScanId, m_pmdid, pdrgppartkeys, ppartcnstrRel);
}

//---------------------------------------------------------------------------
//	@function:
//		CPhysicalJoin::PexprJoinPredOnPartKeys
//
//	@doc:
//		Helper to find join predicates on part keys. Returns NULL if not found
//
//---------------------------------------------------------------------------
CExpression *
CPhysicalJoin::PexprJoinPredOnPartKeys
	(
	IMemoryPool *pmp,
	CExpression *pexprScalar,
	CPartIndexMap *ppimSource,
	ULONG ulPartIndexId,
	CColRefSet *pcrsAllowedRefs
	)
{
	GPOS_ASSERT(NULL != pcrsAllowedRefs);

	CExpression *pexprPred = NULL;
	DrgPpartkeys *pdrgppartkeys = ppimSource->Pdrgppartkeys(ulPartIndexId);
	const ULONG ulKeysets = pdrgppartkeys->UlLength();
	for (ULONG ulKey = 0; NULL == pexprPred && ulKey < ulKeysets; ulKey++)
	{
		// get partition key
		DrgDrgPcr *pdrgpdrgpcrPartKeys = (*pdrgppartkeys)[ulKey]->Pdrgpdrgpcr();

		// try to generate a request with dynamic partition selection
		pexprPred = CPredicateUtils::PexprExtractPredicatesOnPartKeys
										(
										pmp,
										pexprScalar,
										pdrgpdrgpcrPartKeys,
										pcrsAllowedRefs,
										true // fUseConstraints
										);
	}

	return pexprPred;
}

//---------------------------------------------------------------------------
//	@function:
//		CPartInfo::OsPrint
//
//	@doc:
//		Debug print
//
//---------------------------------------------------------------------------
IOstream &
CPartInfo::OsPrint
	(
	IOstream &os
	)
	const
{
	const ULONG ulLength = m_pdrgppartentries->UlLength();
	os << "Part Consumers: ";
	for (ULONG ul = 0; ul < ulLength; ul++)
	{
		CPartInfoEntry *ppartinfoentry = (*m_pdrgppartentries)[ul];
		ppartinfoentry->OsPrint(os);

		// separator
		os << (ul == ulLength - 1 ? "" : ", ");
	}

	os << ", Part Keys: ";
	for (ULONG ulCons = 0; ulCons < ulLength; ulCons++)
	{
		DrgPpartkeys *pdrgppartkeys = Pdrgppartkeys(ulCons);
		os << "(";
		const ULONG ulPartKeys = pdrgppartkeys->UlLength();;
		for (ULONG ulPartKey = 0; ulPartKey < ulPartKeys; ulPartKey++)
		{
			os << *(*pdrgppartkeys)[ulPartKey];
			os << (ulPartKey == ulPartKeys - 1 ? "" : ", ");
		}
		os << ")";
		os << (ulCons == ulLength - 1 ? "" : ", ");
	}

	return os;
}

//---------------------------------------------------------------------------
//	@function:
//		CPhysicalScan::PpimDeriveFromDynamicScan
//
//	@doc:
//		Derive partition index map from a dynamic scan operator
//
//---------------------------------------------------------------------------
CPartIndexMap *
CPhysicalScan::PpimDeriveFromDynamicScan
	(
	IMemoryPool *pmp,
	ULONG ulPartIndexId,
	IMDId *pmdidRel,
	DrgDrgPcr *pdrgpdrgpcrPart,
	ULONG ulSecondaryPartIndexId,
	CPartConstraint *ppartcnstr,
	CPartConstraint *ppartcnstrRel,
	ULONG ulExpectedPropagators
	)
{
	CPartIndexMap *ppim = GPOS_NEW(pmp) CPartIndexMap(pmp);
	PartCnstrMap *ppartcnstrmap = GPOS_NEW(pmp) PartCnstrMap(pmp);
	
	(void) ppartcnstrmap->FInsert(GPOS_NEW(pmp) ULONG(ulSecondaryPartIndexId), ppartcnstr);

	DrgPpartkeys *pdrgppartkeys = GPOS_NEW(pmp) DrgPpartkeys(pmp);
	pdrgppartkeys->Append(GPOS_NEW(pmp) CPartKeys(pdrgpdrgpcrPart));

	ppim->Insert(ulPartIndexId, ppartcnstrmap, CPartIndexMap::EpimConsumer, ulExpectedPropagators, pmdidRel, pdrgppartkeys, ppartcnstrRel);

	return ppim;
}

//---------------------------------------------------------------------------
//	@function:
//		CPhysicalPartitionSelector::PpimDerive
//
//	@doc:
//		Derive partition index map
//
//---------------------------------------------------------------------------
CPartIndexMap *
CPhysicalPartitionSelector::PpimDerive
	(
	IMemoryPool *pmp,
	CExpressionHandle &exprhdl,
	CDrvdPropCtxt *pdpctxt
	)
	const
{
	GPOS_ASSERT(NULL != pdpctxt);

	CDrvdPropPlan *pdpplan = exprhdl.Pdpplan(0 /*ulChildIndex*/);
	CPartIndexMap *ppimInput = pdpplan->Ppim();
	GPOS_ASSERT(NULL != ppimInput);

	ULONG ulExpectedPartitionSelectors = CDrvdPropCtxtPlan::PdpctxtplanConvert(pdpctxt)->UlExpectedPartitionSelectors();

	CPartIndexMap *ppim = ppimInput->PpimPartitionSelector(pmp, m_ulScanId, ulExpectedPartitionSelectors);
	if (!ppim->FContains(m_ulScanId))
	{
		// the consumer of this scan id does not come from the child, i.e. it
		// is on the other side of a join
		Pmdid()->AddRef();
		m_pdrgpdrgpcr->AddRef();
		m_ppartcnstrmap->AddRef();
		m_ppartcnstr->AddRef();

		DrgPpartkeys *pdrgppartkeys = GPOS_NEW(pmp) DrgPpartkeys(pmp);
		pdrgppartkeys->Append(GPOS_NEW(pmp) CPartKeys(m_pdrgpdrgpcr));

		ppim->Insert(m_ulScanId, m_ppartcnstrmap, CPartIndexMap::EpimPropagator, 0 /*ulExpectedPropagators*/, Pmdid(), pdrgppartkeys, m_ppartcnstr);
	}

	return ppim;
}

//---------------------------------------------------------------------------
//	@function:
//		CLogicalSelect::PexprPartPred
//
//	@doc:
//		Compute partition predicate to pass down to n-th child
//
//---------------------------------------------------------------------------
CExpression *
CLogicalSelect::PexprPartPred
	(
	IMemoryPool *pmp,
	CExpressionHandle &exprhdl,
	CExpression *, //pexprInput
	ULONG
#ifdef GPOS_DEBUG
	ulChildIndex
#endif //GPOS_DEBUG
	)
	const
{
	GPOS_ASSERT(0 == ulChildIndex);

	// in case of subquery in select predicate, we cannot extract the whole
	// predicate, and it would not be helpful anyway, so return NULL
	if (exprhdl.Pdpscalar(1 /*ulChildIndex*/)->FHasSubquery())
	{
		return NULL;
	}

	CExpression *pexprScalar = exprhdl.PexprScalarChild(1 /*ulChildIndex*/);
	GPOS_ASSERT(NULL != pexprScalar);

	// get partition keys
	CPartInfo *ppartinfo = exprhdl.Pdprel()->Ppartinfo();
	GPOS_ASSERT(NULL != ppartinfo);

	// we assume that the select is right on top of the dynamic get, so there
	// should be only one part consumer. If there is more, then we are higher up so
	// we do not push down any predicates
	if (1 != ppartinfo->UlConsumers())
	{
		return NULL;
	}

	CExpression *pexprPredOnPartKey = NULL;

	DrgPpartkeys *pdrgppartkeys = ppartinfo->Pdrgppartkeys(0 /*ulPos*/);
	const ULONG ulKeySets = pdrgppartkeys->UlLength();
	for (ULONG ul = 0; NULL == pexprPredOnPartKey && ul < ulKeySets; ul++)
	{
		pexprPredOnPartKey = CPredicateUtils::PexprExtractPredicatesOnPartKeys
												(
												pmp,
												pexprScalar,
												(*pdrgppartkeys)[ul]->Pdrgpdrgpcr(),
												NULL, //pcrsAllowedRefs
												true //fUseConstraints
												);
	}

	return pexprPredOnPartKey;
}

//---------------------------------------------------------------------------
//	@function:
//		CPartIndexMap::AddUnresolved
//
//	@doc:
//		Helper to add part-index id's found in the first map and are
//		unresolved based on the second map
//
//		For example, if the first and second map contain the following entries:
//		pimFst:
//			(partindexid: 1, consumer, part cnstr: 5->[1,3)),
//			(partindexid: 2, consumer, part cnstr: <>),
//		pimSnd:
//			(partindexid: 1, consumer, part cnstr: 6->(4,5))),
//			(partindexid: 2, producer, part cnstr: <>),
//			(partindexid: 3, producer, part cnstr: <>)
//		the result will be:
//			(partindexid: 1, consumer, part cnstr: 5->[1,3), 6->(4,5)),		// part constraint get combined
//			(partindexid: 2, resolver, part cnstr: <>),						// consumer+producer=resolver
//			(partindexid: 3, producer, part cnstr: <>)						// no match for part index id 3: copy out
//
//---------------------------------------------------------------------------
void
CPartIndexMap::AddUnresolved
	(
	IMemoryPool *pmp,
	const CPartIndexMap &pimFst,
	const CPartIndexMap &pimSnd,
	CPartIndexMap* ppimResult
	)
{
	// iterate on first map and lookup entries in second map
	PartIndexMapIter pimiFst(pimFst.m_pim);
	while (pimiFst.FAdvance())
	{
		const CPartTableInfo *pptiFst = pimiFst.Pt();
		ULONG ulScanId = pptiFst->UlScanId();
		EPartIndexManipulator epimFst = pptiFst->Epim();
		ULONG ulPropagatorsFst = pptiFst->UlExpectedPropagators();

		if (NULL != ppimResult->PptiLookup(ulScanId))
		{
			// skip entries already in the result map
			continue;
		}

		// check if entry exists in second map
		CPartTableInfo *pptiSnd = pimSnd.PptiLookup(ulScanId);
		
		EPartIndexManipulator epimResult = epimFst;
		ULONG ulPropagatorsResult = ulPropagatorsFst;
		PartCnstrMap *ppartcnstrmapSnd = NULL;
		if (NULL != pptiSnd)
		{		
			EPartIndexManipulator epimSnd = pptiSnd->Epim();
			ULONG ulPropagatorsSnd = pptiSnd->UlExpectedPropagators();

			GPOS_ASSERT_IMP(epimFst == EpimConsumer && epimSnd == EpimConsumer, ulPropagatorsFst == ulPropagatorsSnd);
			ResolvePropagator(epimFst, ulPropagatorsFst, epimSnd, ulPropagatorsSnd, &epimResult, &ulPropagatorsResult);
			ppartcnstrmapSnd = pptiSnd->Ppartcnstrmap();
		}
		
		// copy mdid and partition columns from part index map entry
		IMDId *pmdid = pptiFst->Pmdid();
		DrgPpartkeys *pdrgppartkeys = pptiFst->Pdrgppartkeys();
		CPartConstraint *ppartcnstrRel = pptiFst->PpartcnstrRel();
		
		PartCnstrMap *ppartcnstrmap = CPartConstraint::PpartcnstrmapCombine(pmp, pptiFst->Ppartcnstrmap(), ppartcnstrmapSnd);

		pmdid->AddRef();
		pdrgppartkeys->AddRef();
		ppartcnstrRel->AddRef();
		
		ppimResult->Insert(ulScanId, ppartcnstrmap, epimResult, ulPropagatorsResult, pmdid, pdrgppartkeys, ppartcnstrRel);
	}
}

//---------------------------------------------------------------------------
//	@function:
//		CPartInfo::AddPartConsumer
//
//	@doc:
//		Add part table consumer
//
//---------------------------------------------------------------------------
void
CPartInfo::AddPartConsumer
	(
	IMemoryPool *pmp,
	ULONG ulScanId,
	IMDId *pmdid,
	DrgDrgPcr *pdrgpdrgpcrPart,
	CPartConstraint *ppartcnstrRel
	)
{
	DrgPpartkeys *pdrgppartkeys = GPOS_NEW(pmp) DrgPpartkeys(pmp);
	pdrgppartkeys->Append(GPOS_NEW(pmp) CPartKeys(pdrgpdrgpcrPart));

	m_pdrgppartentries->Append(GPOS_NEW(pmp) CPartInfoEntry(ulScanId, pmdid, pdrgppartkeys, ppartcnstrRel));
}

//---------------------------------------------------------------------------
//	@function:
//		CPartIndexMap::PpimPartitionSelector
//
//	@doc:
//		Return a new part index map for a partition selector with the given
//		scan id, and the given number of expected selectors above it
//
//---------------------------------------------------------------------------
CPartIndexMap *
CPartIndexMap::PpimPartitionSelector
	(
	IMemoryPool *pmp,
	ULONG ulScanId,
	ULONG ulExpectedFromReq
	)
	const
{
	CPartIndexMap *ppimResult = GPOS_NEW(pmp) CPartIndexMap(pmp);

	PartIndexMapIter pimi(m_pim);
	while (pimi.FAdvance())
	{
		const CPartTableInfo *ppti = pimi.Pt();
		PartCnstrMap *ppartcnstrmap = ppti->Ppartcnstrmap();
		IMDId *pmdid = ppti->Pmdid();
		DrgPpartkeys *pdrgppartkeys = ppti->Pdrgppartkeys();
		CPartConstraint *ppartcnstrRel = ppti->PpartcnstrRel();
		ppartcnstrmap->AddRef();
		pmdid->AddRef();
		pdrgppartkeys->AddRef();
		ppartcnstrRel->AddRef();

		EPartIndexManipulator epim = ppti->Epim();
		ULONG ulExpectedPropagators = ppti->UlExpectedPropagators();
		if (ppti->UlScanId() == ulScanId)
		{
			if (0 == ulExpectedFromReq)
			{
				// this are no other expected partition selectors
				// so this scan id is resolved
				epim = EpimResolver;
				ulExpectedPropagators = 0;
			}
			else
			{
				// this is not resolved yet
				epim = EpimConsumer;
				ulExpectedPropagators = ulExpectedFromReq;
			}
		}

		ppimResult->Insert(ppti->UlScanId(), ppartcnstrmap, epim, ulExpectedPropagators, pmdid, pdrgppartkeys, ppartcnstrRel);
	}

	return ppimResult;
}

//---------------------------------------------------------------------------
//	@function:
//		CPartKeys::PdrgppartkeysCopy
//
//	@doc:
//		Copy array of part keys into given memory pool
//
//---------------------------------------------------------------------------
DrgPpartkeys *
CPartKeys::PdrgppartkeysCopy
	(
	IMemoryPool *pmp,
	const DrgPpartkeys *pdrgppartkeys
	)
{
	GPOS_ASSERT(NULL != pdrgppartkeys);

	DrgPpartkeys *pdrgppartkeysCopy = GPOS_NEW(pmp) DrgPpartkeys(pmp);
	const ULONG ulLength = pdrgppartkeys->UlLength();
	for (ULONG ul = 0; ul < ulLength; ul++)
	{
		pdrgppartkeysCopy->Append((*pdrgppartkeys)[ul]->PpartkeysCopy(pmp));
	}
	return pdrgppartkeysCopy;
}

//---------------------------------------------------------------------------
//	@function:
//		CPartitionPropagationSpec::FRequiresPartitionPropagation
//
//	@doc:
//		Check if given part index id needs to be enforced on top of the given 
//		expression
//
//---------------------------------------------------------------------------
BOOL
CPartitionPropagationSpec::FRequiresPartitionPropagation
	(
	IMemoryPool *pmp, 
	CExpression *pexpr, 
	CExpressionHandle &exprhdl,
	ULONG ulPartIndexId
	)
	const
{
	GPOS_ASSERT(m_ppim->FContains(ulPartIndexId));
	
	// construct partition propagation spec with the given id only, and check if it needs to be 
	// enforced on top
	CPartIndexMap *ppim = GPOS_NEW(pmp) CPartIndexMap(pmp);
	
	IMDId *pmdid = m_ppim->PmdidRel(ulPartIndexId);
	DrgPpartkeys *pdrgppartkeys = m_ppim->Pdrgppartkeys(ulPartIndexId);
	CPartConstraint *ppartcnstr = m_ppim->PpartcnstrRel(ulPartIndexId);
	PartCnstrMap *ppartcnstrmap = m_ppim->Ppartcnstrmap(ulPartIndexId);
	pmdid->AddRef();
	pdrgppartkeys->AddRef();
	ppartcnstr->AddRef();
	ppartcnstrmap->AddRef();
	
	ppim->Insert(ulPartIndexId, ppartcnstrmap, m_ppim->Epim(ulPartIndexId), m_ppim->UlExpectedPropagators(ulPartIndexId), pmdid, pdrgppartkeys, ppartcnstr);
	
	CPartitionPropagationSpec *ppps = GPOS_NEW(pmp) CPartitionPropagationSpec(ppim, GPOS_NEW(pmp) CPartFilterMap(pmp));
	
	CEnfdPartitionPropagation *pepp = GPOS_NEW(pmp) CEnfdPartitionPropagation(ppps, CEnfdPartitionPropagation::EppmSatisfy, GPOS_NEW(pmp) CPartFilterMap(pmp));
	CEnfdProp::EPropEnforcingType epetPartitionPropagation = pepp->Epet(exprhdl, CPhysical::PopConvert(pexpr->Pop()), true /*fPartitionPropagationRequired*/);
	
	pepp->Release();
	
	return CEnfdProp::FEnforce(epetPartitionPropagation);
}

//---------------------------------------------------------------------------
//	@function:
//		CPhysicalNLJoin::PppsRequiredNLJoinChild
//
//	@doc:
//		Compute required partition propagation of the n-th child
//
//---------------------------------------------------------------------------
CPartitionPropagationSpec *
CPhysicalNLJoin::PppsRequiredNLJoinChild
	(
	IMemoryPool *pmp,
	CExpressionHandle &exprhdl,
	CPartitionPropagationSpec *pppsRequired,
	ULONG ulChildIndex,
	DrgPdp *, //pdrgpdpCtxt,
	ULONG ulOptReq
	)
{
	GPOS_ASSERT(NULL != pppsRequired);

	if (1 == ulOptReq)
	{
		// request (1): push partition propagation requests to join's children,
		// do not consider possible dynamic partition elimination using join predicate here,
		// this is handled by optimization request (0) below
		return CPhysical::PppsRequiredPushThruNAry(pmp, exprhdl, pppsRequired, ulChildIndex);
	}
	GPOS_ASSERT(0 == ulOptReq);

	CPartIndexMap *ppim = pppsRequired->Ppim();
	CPartFilterMap *ppfm = pppsRequired->Ppfm();

	DrgPul *pdrgpul = ppim->PdrgpulScanIds(pmp);
	
	CPartIndexMap *ppimResult = GPOS_NEW(pmp) CPartIndexMap(pmp);
	CPartFilterMap *ppfmResult = GPOS_NEW(pmp) CPartFilterMap(pmp);

	CPartInfo *ppartinfoOuter = exprhdl.Pdprel(0)->Ppartinfo();

	CColRefSet *pcrsOutputOuter = exprhdl.Pdprel(0)->PcrsOutput();
	CColRefSet *pcrsOutputInner = exprhdl.Pdprel(1)->PcrsOutput();

	const ULONG ulPartIndexIds = pdrgpul->UlLength();
		
	for (ULONG ul = 0; ul < ulPartIndexIds; ul++)
	{
		ULONG ulPartIndexId = *((*pdrgpul)[ul]);
		if (ppfm->FContainsScanId(ulPartIndexId))
		{
			GPOS_ASSERT(NULL != ppfm->Pexpr(ulPartIndexId));
			// a selection-based propagation request pushed from above: do not propagate any
			// further as the join will reduce cardinality and thus may select more partitions
			// for scanning
			continue;
		}
		
		BOOL fOuterPartConsumer = ppartinfoOuter->FContainsScanId(ulPartIndexId);

		// in order to find interesting join predicates that can be used for DPE,
		// one side of the predicate must be the partition key, while the other side must only contain
		// references from the join child that does not have the partition consumer
		CColRefSet *pcrsAllowedRefs = pcrsOutputOuter;
		if (fOuterPartConsumer)
		{
			pcrsAllowedRefs = pcrsOutputInner;
		}

		if (0 == ulChildIndex && fOuterPartConsumer)
		{
			// always push through required partition propagation for consumers on the
			// outer side of the nested loop join
			DrgPpartkeys *pdrgppartkeys = ppartinfoOuter->PdrgppartkeysByScanId(ulPartIndexId);
			GPOS_ASSERT(NULL != pdrgppartkeys);
			pdrgppartkeys->AddRef();

			ppimResult->AddRequiredPartPropagation(ppim, ulPartIndexId, CPartIndexMap::EppraPreservePropagators, pdrgppartkeys);
		}
		else
		{
			// check if there is an interesting condition involving the partition key
			CExpression *pexprScalar = exprhdl.PexprScalarChild(2 /*ulChildIndex*/);
			AddFilterOnPartKey(pmp, true /*fNLJoin*/, pexprScalar, ppim, ppfm, ulChildIndex, ulPartIndexId, fOuterPartConsumer, ppimResult, ppfmResult, pcrsAllowedRefs);
		}
	}
	
	pdrgpul->Release();

	return GPOS_NEW(pmp) CPartitionPropagationSpec(ppimResult, ppfmResult);
}

//---------------------------------------------------------------------------
//	@function:
//		CPhysicalHashJoin::PppsRequiredCompute
//
//	@doc:
//		Compute required partition propagation of the n-th child
//
//---------------------------------------------------------------------------
CPartitionPropagationSpec *
CPhysicalHashJoin::PppsRequiredCompute
	(
	IMemoryPool *pmp,
	CExpressionHandle &exprhdl,
	CPartitionPropagationSpec *pppsRequired,
	ULONG ulChildIndex
	)
{
	CPartIndexMap *ppim = pppsRequired->Ppim();
	CPartFilterMap *ppfm = pppsRequired->Ppfm();

	DrgPul *pdrgpul = ppim->PdrgpulScanIds(pmp);

	CPartIndexMap *ppimResult = GPOS_NEW(pmp) CPartIndexMap(pmp);
	CPartFilterMap *ppfmResult = GPOS_NEW(pmp) CPartFilterMap(pmp);

	// get outer partition consumers
	CPartInfo *ppartinfo = exprhdl.Pdprel(0)->Ppartinfo();

	CColRefSet *pcrsOutputOuter = exprhdl.Pdprel(0)->PcrsOutput();
	CColRefSet *pcrsOutputInner = exprhdl.Pdprel(1)->PcrsOutput();

	const ULONG ulPartIndexIds = pdrgpul->UlLength();

	for (ULONG ul = 0; ul < ulPartIndexIds; ul++)
	{
		ULONG ulPartIndexId = *((*pdrgpul)[ul]);

		if (ppfm->FContainsScanId(ulPartIndexId))
		{
			GPOS_ASSERT(NULL != ppfm->Pexpr(ulPartIndexId));
			// a selection-based propagation request pushed from above: do not propagate any
			// further as the join will reduce cardinality and thus may select more partitions
			// for scanning
			continue;
		}
		
		BOOL fOuterPartConsumer = ppartinfo->FContainsScanId(ulPartIndexId);

		// in order to find interesting join predicates that can be used for DPE,
		// one side of the predicate must be the partition key, while the other side must only contain
		// references from the join child that does not have the partition consumer
		CColRefSet *pcrsAllowedRefs = pcrsOutputOuter;
		if (fOuterPartConsumer)
		{
			pcrsAllowedRefs = pcrsOutputInner;
		}

		if (1 == ulChildIndex && !fOuterPartConsumer)
		{
			// always push through required partition propagation for consumers on the
			// inner side of the hash join
			DrgPpartkeys *pdrgppartkeys = exprhdl.Pdprel(1 /*ulChildIndex*/)->Ppartinfo()->PdrgppartkeysByScanId(ulPartIndexId);
			GPOS_ASSERT(NULL != pdrgppartkeys);
			pdrgppartkeys->AddRef();

			ppimResult->AddRequiredPartPropagation(ppim, ulPartIndexId, CPartIndexMap::EppraPreservePropagators, pdrgppartkeys);
		}
		else
		{	
			// look for a filter on the part key
			CExpression *pexprScalar = exprhdl.PexprScalarChild(2 /*ulChildIndex*/);
			AddFilterOnPartKey(pmp, false /*fNLJoin*/, pexprScalar, ppim, ppfm, ulChildIndex, ulPartIndexId, fOuterPartConsumer, ppimResult, ppfmResult, pcrsAllowedRefs);
		}
	}

	pdrgpul->Release();

	return GPOS_NEW(pmp) CPartitionPropagationSpec(ppimResult, ppfmResult);
}