//---------------------------------------------------------------------------
// @function:
// CConstraint::PcnstrConjDisjRemapForColumn
//
// @doc:
// Return a copy of the conjunction/disjunction constraint for a different column
//
//---------------------------------------------------------------------------
CConstraint *
CConstraint::PcnstrConjDisjRemapForColumn
(
IMemoryPool *pmp,
CColRef *pcr,
DrgPcnstr *pdrgpcnstr,
BOOL fConj
)
const
{
GPOS_ASSERT(NULL != pcr);
DrgPcnstr *pdrgpcnstrNew = GPOS_NEW(pmp) DrgPcnstr(pmp);
const ULONG ulLen = pdrgpcnstr->UlLength();
for (ULONG ul = 0; ul < ulLen; ul++)
{
// clone child
CConstraint *pcnstrChild = (*pdrgpcnstr)[ul]->PcnstrRemapForColumn(pmp, pcr);
GPOS_ASSERT(NULL != pcnstrChild);
pdrgpcnstrNew->Append(pcnstrChild);
}
if (fConj)
{
return PcnstrConjunction(pmp, pdrgpcnstrNew);
}
return PcnstrDisjunction(pmp, pdrgpcnstrNew);
}
// mapping between columns and single column constraints in array of constraints
static
HMColConstr *
PhmcolconstrSingleColConstr
(
IMemoryPool *pmp,
DrgPcnstr *drgPcnstr
)
{
CAutoRef<DrgPcnstr> arpdrgpcnstr(drgPcnstr);
HMColConstr *phmcolconstr = GPOS_NEW(pmp) HMColConstr(pmp);
const ULONG ulLen = arpdrgpcnstr->UlLength();
for (ULONG ul = 0; ul < ulLen; ul++)
{
CConstraint *pcnstrChild = (*arpdrgpcnstr)[ul];
CColRefSet *pcrs = pcnstrChild->PcrsUsed();
if (1 == pcrs->CElements())
{
CColRef *pcr = pcrs->PcrFirst();
DrgPcnstr *pcnstrMapped = phmcolconstr->PtLookup(pcr);
if (NULL == pcnstrMapped)
{
pcnstrMapped = GPOS_NEW(pmp) DrgPcnstr(pmp);
phmcolconstr->FInsert(pcr, pcnstrMapped);
}
pcnstrChild->AddRef();
pcnstrMapped->Append(pcnstrChild);
}
}
return phmcolconstr;
}
//---------------------------------------------------------------------------
// @function:
// CConstraint::PdrgpcnstrOnColumn
//
// @doc:
// Return a subset of the given constraints which reference the
// given column
//
//---------------------------------------------------------------------------
DrgPcnstr *
CConstraint::PdrgpcnstrOnColumn
(
IMemoryPool *pmp,
DrgPcnstr *pdrgpcnstr,
CColRef *pcr,
BOOL fExclusive // returned constraints must reference ONLY the given col
)
{
DrgPcnstr *pdrgpcnstrSubset = GPOS_NEW(pmp) DrgPcnstr(pmp);
const ULONG ulLen = pdrgpcnstr->UlLength();
for (ULONG ul = 0; ul < ulLen; ul++)
{
CConstraint *pcnstr = (*pdrgpcnstr)[ul];
CColRefSet *pcrs = pcnstr->PcrsUsed();
// if the fExclusive flag is true, then pcr must be the only column
if (pcrs->FMember(pcr) && (!fExclusive || 1 == pcrs->CElements()))
{
pcnstr->AddRef();
pdrgpcnstrSubset->Append(pcnstr);
}
}
return pdrgpcnstrSubset;
}
//---------------------------------------------------------------------------
// @function:
// CLogicalSetOp::PdrgpcnstrColumn
//
// @doc:
// Get constraints for a given output column from all children
//
//---------------------------------------------------------------------------
DrgPcnstr *
CLogicalSetOp::PdrgpcnstrColumn
(
IMemoryPool *pmp,
CExpressionHandle &exprhdl,
ULONG ulColIndex,
ULONG ulStart
)
const
{
DrgPcnstr *pdrgpcnstr = GPOS_NEW(pmp) DrgPcnstr(pmp);
CColRef *pcr = (*m_pdrgpcrOutput)[ulColIndex];
if (!CUtils::FConstrainableType(pcr->Pmdtype()->Pmdid()))
{
return pdrgpcnstr;
}
const ULONG ulChildren = exprhdl.UlArity();
for (ULONG ul = ulStart; ul < ulChildren; ul++)
{
CConstraint *pcnstr = PcnstrColumn(pmp, exprhdl, ulColIndex, ul);
if (NULL == pcnstr)
{
pcnstr = CConstraintInterval::PciUnbounded(pmp, pcr, true /*fIsNull*/);
}
GPOS_ASSERT (NULL != pcnstr);
pdrgpcnstr->Append(pcnstr);
}
return pdrgpcnstr;
}
DrgPcnstr *
CColConstraintsHashMapper::PdrgPcnstrLookup
(
CColRef *pcr
)
{
DrgPcnstr *pdrgpcnstrCol = m_phmColConstr->PtLookup(pcr);
pdrgpcnstrCol->AddRef();
return pdrgpcnstrCol;
}
//---------------------------------------------------------------------------
// @function:
// CConstraint::PcnstrFromScalarCmp
//
// @doc:
// Create constraint from scalar comparison
//
//---------------------------------------------------------------------------
CConstraint *
CConstraint::PcnstrFromScalarCmp
(
IMemoryPool *pmp,
CExpression *pexpr,
DrgPcrs **ppdrgpcrs // output equivalence classes
)
{
GPOS_ASSERT(NULL != pexpr);
GPOS_ASSERT(CUtils::FScalarCmp(pexpr));
GPOS_ASSERT(NULL != ppdrgpcrs);
GPOS_ASSERT(NULL == *ppdrgpcrs);
CExpression *pexprLeft = (*pexpr)[0];
CExpression *pexprRight = (*pexpr)[1];
// check if the scalar comparison is over scalar idents
if (COperator::EopScalarIdent == pexprLeft->Pop()->Eopid()
&& COperator::EopScalarIdent == pexprRight->Pop()->Eopid())
{
CScalarIdent *popScIdLeft = CScalarIdent::PopConvert((*pexpr)[0]->Pop());
const CColRef *pcrLeft = popScIdLeft->Pcr();
CScalarIdent *popScIdRight = CScalarIdent::PopConvert((*pexpr)[1]->Pop());
const CColRef *pcrRight = popScIdRight->Pcr();
if (!CUtils::FConstrainableType(pcrLeft->Pmdtype()->Pmdid()) ||
!CUtils::FConstrainableType(pcrRight->Pmdtype()->Pmdid()))
{
return NULL;
}
*ppdrgpcrs = GPOS_NEW(pmp) DrgPcrs(pmp);
if (CPredicateUtils::FEquality(pexpr))
{
// col1 = col2
CColRefSet *pcrsNew = GPOS_NEW(pmp) CColRefSet(pmp);
pcrsNew->Include(pcrLeft);
pcrsNew->Include(pcrRight);
(*ppdrgpcrs)->Append(pcrsNew);
}
// create NOT NULL constraints to both columns
DrgPcnstr *pdrgpcnstr = GPOS_NEW(pmp) DrgPcnstr(pmp);
pdrgpcnstr->Append(CConstraintInterval::PciUnbounded(pmp, pcrLeft, false /*fIncludesNull*/));
pdrgpcnstr->Append(CConstraintInterval::PciUnbounded(pmp, pcrRight, false /*fIncludesNull*/));
return CConstraint::PcnstrConjunction(pmp, pdrgpcnstr);
}
// TODO: , May 28, 2012; add support for other cases besides (col cmp col)
return NULL;
}
//---------------------------------------------------------------------------
// @function:
// CConstraint::PcnstrFromScalarArrayCmp
//
// @doc:
// Create constraint from scalar array comparison expression
//
//---------------------------------------------------------------------------
CConstraint *
CConstraint::PcnstrFromScalarArrayCmp
(
IMemoryPool *pmp,
CExpression *pexpr,
CColRef *pcr
)
{
GPOS_ASSERT(NULL != pexpr);
GPOS_ASSERT(CUtils::FScalarArrayCmp(pexpr));
CScalarArrayCmp *popScArrayCmp = CScalarArrayCmp::PopConvert(pexpr->Pop());
CScalarArrayCmp::EArrCmpType earrccmpt = popScArrayCmp->Earrcmpt();
if ((CScalarArrayCmp::EarrcmpAny == earrccmpt || CScalarArrayCmp::EarrcmpAll == earrccmpt) &&
CPredicateUtils::FCompareIdentToConstArray(pexpr))
{
// column
#ifdef GPOS_DEBUG
CScalarIdent *popScId = CScalarIdent::PopConvert((*pexpr)[0]->Pop());
GPOS_ASSERT (pcr == (CColRef *) popScId->Pcr());
#endif // GPOS_DEBUG
// get comparison type
IMDType::ECmpType ecmpt = CUtils::Ecmpt(popScArrayCmp->PmdidOp());
CExpression *pexprArray = (*pexpr)[1];
DrgPcnstr *pdrgpcnstr = GPOS_NEW(pmp) DrgPcnstr(pmp);
const ULONG ulArity = pexprArray->UlArity();
for (ULONG ul = 0; ul < ulArity; ul++)
{
GPOS_ASSERT(CUtils::FScalarConst((*pexprArray)[ul]) && "expecting a constant");
CScalarConst *popScConst = CScalarConst::PopConvert((*pexprArray)[ul]->Pop());
CConstraintInterval *pci = CConstraintInterval::PciIntervalFromColConstCmp(pmp, pcr, ecmpt, popScConst);
pdrgpcnstr->Append(pci);
}
if (earrccmpt == CScalarArrayCmp::EarrcmpAny)
{
// predicate is of the form 'A IN (1,2,3)'
// return a disjunction of ranges {[1,1], [2,2], [3,3]}
return GPOS_NEW(pmp) CConstraintDisjunction(pmp, pdrgpcnstr);
}
// predicate is of the form 'A NOT IN (1,2,3)'
// return a conjunctive negation on {[1,1], [2,2], [3,3]}
return GPOS_NEW(pmp) CConstraintConjunction(pmp, pdrgpcnstr);
}
return NULL;
}
//---------------------------------------------------------------------------
// @function:
// CLogical::PpcDeriveConstraintFromTableWithPredicates
//
// @doc:
// Derive constraint property from a table/index get with predicates
//
//---------------------------------------------------------------------------
CPropConstraint *
CLogical::PpcDeriveConstraintFromTableWithPredicates
(
IMemoryPool *pmp,
CExpressionHandle &exprhdl,
const CTableDescriptor *ptabdesc,
const DrgPcr *pdrgpcrOutput
)
{
DrgPcnstr *pdrgpcnstr = GPOS_NEW(pmp) DrgPcnstr(pmp);
CPropConstraint *ppcTable = PpcDeriveConstraintFromTable(pmp, ptabdesc, pdrgpcrOutput);
CConstraint *pcnstrTable = ppcTable->Pcnstr();
if (NULL != pcnstrTable)
{
pcnstrTable->AddRef();
pdrgpcnstr->Append(pcnstrTable);
}
DrgPcrs *pdrgpcrsEquivClassesTable = ppcTable->PdrgpcrsEquivClasses();
CPropConstraint *ppcnstrCond = PpcDeriveConstraintFromPredicates(pmp, exprhdl);
CConstraint *pcnstrCond = ppcnstrCond->Pcnstr();
if (NULL != pcnstrCond)
{
pcnstrCond->AddRef();
pdrgpcnstr->Append(pcnstrCond);
}
else if (NULL == pcnstrTable)
{
ppcTable->Release();
pdrgpcnstr->Release();
return ppcnstrCond;
}
DrgPcrs *pdrgpcrsCond = ppcnstrCond->PdrgpcrsEquivClasses();
DrgPcrs *pdrgpcrs = CUtils::PdrgpcrsMergeEquivClasses(pmp, pdrgpcrsEquivClassesTable, pdrgpcrsCond);
CPropConstraint *ppc = GPOS_NEW(pmp) CPropConstraint(pmp, pdrgpcrs, CConstraint::PcnstrConjunction(pmp, pdrgpcnstr));
ppcnstrCond->Release();
ppcTable->Release();
return ppc;
}
//---------------------------------------------------------------------------
// @function:
// CLogicalSetOp::PpcDeriveConstraintIntersectUnion
//
// @doc:
// Derive constraint property for intersect and union operators
//
//---------------------------------------------------------------------------
CPropConstraint *
CLogicalSetOp::PpcDeriveConstraintIntersectUnion
(
IMemoryPool *pmp,
CExpressionHandle &exprhdl,
BOOL fIntersect
)
const
{
const ULONG ulCols = m_pdrgpcrOutput->UlLength();
DrgPcnstr *pdrgpcnstr = GPOS_NEW(pmp) DrgPcnstr(pmp);
for (ULONG ul = 0; ul < ulCols; ul++)
{
// get constraints for this column from all children
DrgPcnstr *pdrgpcnstrCol = PdrgpcnstrColumn(pmp, exprhdl, ul, 0 /*ulStart*/);
CConstraint *pcnstrCol = NULL;
if (fIntersect)
{
pcnstrCol = CConstraint::PcnstrConjunction(pmp, pdrgpcnstrCol);
}
else
{
pcnstrCol = CConstraint::PcnstrDisjunction(pmp, pdrgpcnstrCol);
}
if (NULL != pcnstrCol)
{
pdrgpcnstr->Append(pcnstrCol);
}
}
CConstraint *pcnstrAll = CConstraint::PcnstrConjunction(pmp, pdrgpcnstr);
DrgPcrs *pdrgpcrs = PdrgpcrsOutputEquivClasses(pmp, exprhdl, fIntersect);
return GPOS_NEW(pmp) CPropConstraint(pmp, pdrgpcrs, pcnstrAll);
}
//---------------------------------------------------------------------------
// @function:
// CConstraint::PdrgpcnstrFlatten
//
// @doc:
// Flatten an array of constraints to be used as children for a conjunction
// or disjunction. If any of these children is of the same type then use
// its children directly instead of having multiple levels of the same type
//
//---------------------------------------------------------------------------
DrgPcnstr *
CConstraint::PdrgpcnstrFlatten
(
IMemoryPool *pmp,
DrgPcnstr *pdrgpcnstr,
EConstraintType ect
)
const
{
DrgPcnstr *pdrgpcnstrNew = GPOS_NEW(pmp) DrgPcnstr(pmp);
const ULONG ulLen = pdrgpcnstr->UlLength();
for (ULONG ul = 0; ul < ulLen; ul++)
{
CConstraint *pcnstrChild = (*pdrgpcnstr)[ul];
EConstraintType ectChild = pcnstrChild->Ect();
if (EctConjunction == ectChild && EctConjunction == ect)
{
CConstraintConjunction *pcconj = (CConstraintConjunction *)pcnstrChild;
CUtils::AddRefAppend<CConstraint, CleanupRelease>(pdrgpcnstrNew, pcconj->Pdrgpcnstr());
}
else if (EctDisjunction == ectChild && EctDisjunction == ect)
{
CConstraintDisjunction *pcdisj = (CConstraintDisjunction *)pcnstrChild;
CUtils::AddRefAppend<CConstraint, CleanupRelease>(pdrgpcnstrNew, pcdisj->Pdrgpcnstr());
}
else
{
pcnstrChild->AddRef();
pdrgpcnstrNew->Append(pcnstrChild);
}
}
pdrgpcnstr->Release();
return PdrgpcnstrDeduplicate(pmp, pdrgpcnstrNew, ect);
}
//---------------------------------------------------------------------------
// @function:
// CConstraint::PdrgpcnstrDeduplicate
//
// @doc:
// Simplify an array of constraints to be used as children for a conjunction
// or disjunction. If there are two or more elements that reference only one
// particular column, these constraints are combined into one
//
//---------------------------------------------------------------------------
DrgPcnstr *
CConstraint::PdrgpcnstrDeduplicate
(
IMemoryPool *pmp,
DrgPcnstr *pdrgpcnstr,
EConstraintType ect
)
const
{
DrgPcnstr *pdrgpcnstrNew = GPOS_NEW(pmp) DrgPcnstr(pmp);
CColRefSet *pcrsDeduped = GPOS_NEW(pmp) CColRefSet(pmp);
const ULONG ulLen = pdrgpcnstr->UlLength();
for (ULONG ul = 0; ul < ulLen; ul++)
{
CConstraint *pcnstrChild = (*pdrgpcnstr)[ul];
CColRefSet *pcrs = pcnstrChild->PcrsUsed();
// we only simplify constraints that reference a single column, otherwise
// we add constraint as is
if (1 < pcrs->CElements())
{
pcnstrChild->AddRef();
pdrgpcnstrNew->Append(pcnstrChild);
continue;
}
CColRef *pcr = pcrs->PcrFirst();
if (pcrsDeduped->FMember(pcr))
{
// current constraint has already been combined with a previous one
continue;
}
// get all constraints from the input array that reference this column
DrgPcnstr *pdrgpcnstrCol = PdrgpcnstrOnColumn(pmp, pdrgpcnstr, pcr, true /*fExclusive*/);
if (1 == pdrgpcnstrCol->UlLength())
{
// if there is only one such constraint, then no simplification
// for this column
pdrgpcnstrCol->Release();
pcnstrChild->AddRef();
pdrgpcnstrNew->Append(pcnstrChild);
continue;
}
CExpression *pexpr = NULL;
if (EctConjunction == ect)
{
pexpr = PexprScalarConjDisj(pmp, pdrgpcnstrCol, true /*fConj*/);
}
else
{
GPOS_ASSERT(EctDisjunction == ect);
pexpr = PexprScalarConjDisj(pmp, pdrgpcnstrCol, false /*fConj*/);
}
pdrgpcnstrCol->Release();
GPOS_ASSERT(NULL != pexpr);
CConstraint *pcnstrNew = CConstraintInterval::PciIntervalFromScalarExpr(pmp, pexpr, pcr);
GPOS_ASSERT(NULL != pcnstrNew);
pexpr->Release();
pdrgpcnstrNew->Append(pcnstrNew);
pcrsDeduped->Include(pcr);
}
pcrsDeduped->Release();
pdrgpcnstr->Release();
return pdrgpcnstrNew;
}
//---------------------------------------------------------------------------
// @function:
// CConstraint::PcnstrFromScalarBoolOp
//
// @doc:
// Create constraint from scalar boolean expression
//
//---------------------------------------------------------------------------
CConstraint *
CConstraint::PcnstrFromScalarBoolOp
(
IMemoryPool *pmp,
CExpression *pexpr,
DrgPcrs **ppdrgpcrs // output equivalence classes
)
{
GPOS_ASSERT(NULL != pexpr);
GPOS_ASSERT(CUtils::FScalarBoolOp(pexpr));
GPOS_ASSERT(NULL != ppdrgpcrs);
GPOS_ASSERT(NULL == *ppdrgpcrs);
*ppdrgpcrs = GPOS_NEW(pmp) DrgPcrs(pmp);
DrgPcnstr *pdrgpcnstr = GPOS_NEW(pmp) DrgPcnstr(pmp);
const ULONG ulArity= pexpr->UlArity();
for (ULONG ul = 0; ul < ulArity; ul++)
{
DrgPcrs *pdrgpcrsChild = NULL;
CConstraint *pcnstrChild = PcnstrFromScalarExpr(pmp, (*pexpr)[ul], &pdrgpcrsChild);
if (NULL == pcnstrChild || pcnstrChild->FUnbounded())
{
CRefCount::SafeRelease(pcnstrChild);
CRefCount::SafeRelease(pdrgpcrsChild);
if (CPredicateUtils::FOr(pexpr))
{
pdrgpcnstr->Release();
return NULL;
}
continue;
}
GPOS_ASSERT(NULL != pdrgpcrsChild);
pdrgpcnstr->Append(pcnstrChild);
DrgPcrs *pdrgpcrsMerged = PdrgpcrsMergeFromBoolOp(pmp, pexpr, *ppdrgpcrs, pdrgpcrsChild);
(*ppdrgpcrs)->Release();
*ppdrgpcrs = pdrgpcrsMerged;
pdrgpcrsChild->Release();
}
const ULONG ulLen = pdrgpcnstr->UlLength();
if (0 == ulLen)
{
pdrgpcnstr->Release();
return NULL;
}
if (1 == ulLen)
{
CConstraint *pcnstrChild = (*pdrgpcnstr)[0];
pcnstrChild->AddRef();
pdrgpcnstr->Release();
if (CPredicateUtils::FNot(pexpr))
{
return GPOS_NEW(pmp) CConstraintNegation(pmp, pcnstrChild);
}
return pcnstrChild;
}
// we know we have more than one child
if (CPredicateUtils::FAnd(pexpr))
{
return GPOS_NEW(pmp) CConstraintConjunction(pmp, pdrgpcnstr);
}
if (CPredicateUtils::FOr(pexpr))
{
return GPOS_NEW(pmp) CConstraintDisjunction(pmp, pdrgpcnstr);
}
return NULL;
}
//---------------------------------------------------------------------------
// @function:
// CLogical::PpcDeriveConstraintRestrict
//
// @doc:
// Derive constraint property only on the given columns
//
//---------------------------------------------------------------------------
CPropConstraint *
CLogical::PpcDeriveConstraintRestrict
(
IMemoryPool *pmp,
CExpressionHandle &exprhdl,
CColRefSet *pcrsOutput
)
{
// constraint property from relational child
CPropConstraint *ppc = exprhdl.Pdprel(0)->Ppc();
DrgPcrs *pdrgpcrs = ppc->PdrgpcrsEquivClasses();
// construct new array of equivalence classes
DrgPcrs *pdrgpcrsNew = GPOS_NEW(pmp) DrgPcrs(pmp);
const ULONG ulLen = pdrgpcrs->UlLength();
for (ULONG ul = 0; ul < ulLen; ul++)
{
CColRefSet *pcrsEquiv = GPOS_NEW(pmp) CColRefSet(pmp);
pcrsEquiv->Include((*pdrgpcrs)[ul]);
pcrsEquiv->Intersection(pcrsOutput);
if (0 < pcrsEquiv->CElements())
{
pdrgpcrsNew->Append(pcrsEquiv);
}
else
{
pcrsEquiv->Release();
}
}
CConstraint *pcnstrChild = ppc->Pcnstr();
if (NULL == pcnstrChild)
{
return GPOS_NEW(pmp) CPropConstraint(pmp, pdrgpcrsNew, NULL);
}
DrgPcnstr *pdrgpcnstr = GPOS_NEW(pmp) DrgPcnstr(pmp);
// include only constraints on given columns
CColRefSetIter crsi(*pcrsOutput);
while (crsi.FAdvance())
{
CColRef *pcr = crsi.Pcr();
CConstraint *pcnstrCol = pcnstrChild->Pcnstr(pmp, pcr);
if (NULL == pcnstrCol)
{
continue;
}
if (pcnstrCol->FUnbounded())
{
pcnstrCol->Release();
continue;
}
pdrgpcnstr->Append(pcnstrCol);
}
CConstraint *pcnstr = CConstraint::PcnstrConjunction(pmp, pdrgpcnstr);
return GPOS_NEW(pmp) CPropConstraint(pmp, pdrgpcrsNew, pcnstr);
}
//---------------------------------------------------------------------------
// @function:
// CLogical::PpcDeriveConstraintFromTable
//
// @doc:
// Derive constraint property from a table/index get
//
//---------------------------------------------------------------------------
CPropConstraint *
CLogical::PpcDeriveConstraintFromTable
(
IMemoryPool *pmp,
const CTableDescriptor *ptabdesc,
const DrgPcr *pdrgpcrOutput
)
{
DrgPcrs *pdrgpcrs = GPOS_NEW(pmp) DrgPcrs(pmp);
DrgPcnstr *pdrgpcnstr = GPOS_NEW(pmp) DrgPcnstr(pmp);
const DrgPcoldesc *pdrgpcoldesc = ptabdesc->Pdrgpcoldesc();
const ULONG ulCols = pdrgpcoldesc->UlLength();
DrgPcr *pdrgpcrNonSystem = GPOS_NEW(pmp) DrgPcr(pmp);
for (ULONG ul = 0; ul < ulCols; ul++)
{
CColumnDescriptor *pcoldesc = (*pdrgpcoldesc)[ul];
CColRef *pcr = (*pdrgpcrOutput)[ul];
// we are only interested in non-system columns that are defined as
// being NOT NULL
if (pcoldesc->FSystemColumn())
{
continue;
}
pdrgpcrNonSystem->Append(pcr);
if (pcoldesc->FNullable())
{
continue;
}
// add a "not null" constraint and an equivalence class
CConstraint * pcnstr = CConstraintInterval::PciUnbounded(pmp, pcr, false /*fIncludesNull*/);
if (pcnstr == NULL)
{
continue;
}
pdrgpcnstr->Append(pcnstr);
CColRefSet *pcrsEquiv = GPOS_NEW(pmp) CColRefSet(pmp);
pcrsEquiv->Include(pcr);
pdrgpcrs->Append(pcrsEquiv);
}
CMDAccessor *pmda = COptCtxt::PoctxtFromTLS()->Pmda();
const IMDRelation *pmdrel = pmda->Pmdrel(ptabdesc->Pmdid());
const ULONG ulCheckConstraint = pmdrel->UlCheckConstraints();
for (ULONG ul = 0; ul < ulCheckConstraint; ul++)
{
IMDId *pmdidCheckConstraint = pmdrel->PmdidCheckConstraint(ul);
const IMDCheckConstraint *pmdCheckConstraint = pmda->Pmdcheckconstraint(pmdidCheckConstraint);
// extract the check constraint expression
CExpression *pexprCheckConstraint = pmdCheckConstraint->Pexpr(pmp, pmda, pdrgpcrNonSystem);
GPOS_ASSERT(NULL != pexprCheckConstraint);
GPOS_ASSERT(CUtils::FPredicate(pexprCheckConstraint));
DrgPcrs *pdrgpcrsChild = NULL;
CConstraint *pcnstr = CConstraint::PcnstrFromScalarExpr(pmp, pexprCheckConstraint, &pdrgpcrsChild);
if (NULL != pcnstr)
{
pdrgpcnstr->Append(pcnstr);
// merge with the equivalence classes we have so far
DrgPcrs *pdrgpcrsMerged = CUtils::PdrgpcrsMergeEquivClasses(pmp, pdrgpcrs, pdrgpcrsChild);
pdrgpcrs->Release();
pdrgpcrs = pdrgpcrsMerged;
}
CRefCount::SafeRelease(pdrgpcrsChild);
pexprCheckConstraint->Release();
}
pdrgpcrNonSystem->Release();
return GPOS_NEW(pmp) CPropConstraint(pmp, pdrgpcrs, CConstraint::PcnstrConjunction(pmp, pdrgpcnstr));
}
//---------------------------------------------------------------------------
// @function:
// CLogical::PpcDeriveConstraintFromPredicates
//
// @doc:
// Derive constraint property when expression has relational children and
// scalar children (predicates)
//
//---------------------------------------------------------------------------
CPropConstraint *
CLogical::PpcDeriveConstraintFromPredicates
(
IMemoryPool *pmp,
CExpressionHandle &exprhdl
)
{
DrgPcrs *pdrgpcrs = GPOS_NEW(pmp) DrgPcrs(pmp);
DrgPcnstr *pdrgpcnstr = GPOS_NEW(pmp) DrgPcnstr(pmp);
// collect constraint properties from relational children
// and predicates from scalar children
const ULONG ulArity = exprhdl.UlArity();
for (ULONG ul = 0; ul < ulArity; ul++)
{
if (exprhdl.FScalarChild(ul))
{
CExpression *pexprScalar = exprhdl.PexprScalarChild(ul);
// make sure it is a predicate... boolop, cmp, nulltest
if (NULL == pexprScalar || !CUtils::FPredicate(pexprScalar))
{
continue;
}
DrgPcrs *pdrgpcrsChild = NULL;
CConstraint *pcnstr = CConstraint::PcnstrFromScalarExpr(pmp, pexprScalar, &pdrgpcrsChild);
if (NULL != pcnstr)
{
pdrgpcnstr->Append(pcnstr);
// merge with the equivalence classes we have so far
DrgPcrs *pdrgpcrsMerged = CUtils::PdrgpcrsMergeEquivClasses(pmp, pdrgpcrs, pdrgpcrsChild);
pdrgpcrs->Release();
pdrgpcrs = pdrgpcrsMerged;
}
CRefCount::SafeRelease(pdrgpcrsChild);
}
else
{
CDrvdPropRelational *pdprel = exprhdl.Pdprel(ul);
CPropConstraint *ppc = pdprel->Ppc();
// equivalence classes coming from child
DrgPcrs *pdrgpcrsChild = ppc->PdrgpcrsEquivClasses();
// merge with the equivalence classes we have so far
DrgPcrs *pdrgpcrsMerged = CUtils::PdrgpcrsMergeEquivClasses(pmp, pdrgpcrs, pdrgpcrsChild);
pdrgpcrs->Release();
pdrgpcrs = pdrgpcrsMerged;
// constraint coming from child
CConstraint *pcnstr = ppc->Pcnstr();
if (NULL != pcnstr)
{
pcnstr->AddRef();
pdrgpcnstr->Append(pcnstr);
}
}
}
CConstraint *pcnstrNew = CConstraint::PcnstrConjunction(pmp, pdrgpcnstr);
return GPOS_NEW(pmp) CPropConstraint(pmp, pdrgpcrs, pcnstrNew);
}
//---------------------------------------------------------------------------
// @function:
// CConstraint::PcnstrFromScalarArrayCmp
//
// @doc:
// Create constraint from scalar array comparison expression
//
//---------------------------------------------------------------------------
CConstraint *
CConstraint::PcnstrFromScalarArrayCmp
(
IMemoryPool *pmp,
CExpression *pexpr,
CColRef *pcr
)
{
GPOS_ASSERT(NULL != pexpr);
GPOS_ASSERT(CUtils::FScalarArrayCmp(pexpr));
CScalarArrayCmp *popScArrayCmp = CScalarArrayCmp::PopConvert(pexpr->Pop());
CScalarArrayCmp::EArrCmpType earrccmpt = popScArrayCmp->Earrcmpt();
if ((CScalarArrayCmp::EarrcmpAny == earrccmpt || CScalarArrayCmp::EarrcmpAll == earrccmpt) &&
CPredicateUtils::FCompareIdentToConstArray(pexpr))
{
// column
#ifdef GPOS_DEBUG
CScalarIdent *popScId = CScalarIdent::PopConvert((*pexpr)[0]->Pop());
GPOS_ASSERT (pcr == (CColRef *) popScId->Pcr());
#endif // GPOS_DEBUG
// get comparison type
IMDType::ECmpType ecmpt = CUtils::Ecmpt(popScArrayCmp->PmdidOp());
CExpression *pexprArray = CUtils::PexprScalarArrayChild(pexpr);
const ULONG ulArity = CUtils::UlScalarArrayArity(pexprArray);
// When array size exceeds the threshold, don't expand it into a DNF
COptimizerConfig *poconf = COptCtxt::PoctxtFromTLS()->Poconf();
ULONG ulArrayExpansionThreshold = poconf->Phint()->UlArrayExpansionThreshold();
if (ulArity > ulArrayExpansionThreshold)
{
return NULL;
}
DrgPcnstr *pdrgpcnstr = GPOS_NEW(pmp) DrgPcnstr(pmp);
for (ULONG ul = 0; ul < ulArity; ul++)
{
CScalarConst *popScConst = CUtils::PScalarArrayConstChildAt(pexprArray,ul);
CConstraintInterval *pci = CConstraintInterval::PciIntervalFromColConstCmp(pmp, pcr, ecmpt, popScConst);
pdrgpcnstr->Append(pci);
}
if (earrccmpt == CScalarArrayCmp::EarrcmpAny)
{
// predicate is of the form 'A IN (1,2,3)'
// return a disjunction of ranges {[1,1], [2,2], [3,3]}
return GPOS_NEW(pmp) CConstraintDisjunction(pmp, pdrgpcnstr);
}
// predicate is of the form 'A NOT IN (1,2,3)'
// return a conjunctive negation on {[1,1], [2,2], [3,3]}
return GPOS_NEW(pmp) CConstraintConjunction(pmp, pdrgpcnstr);
}
return NULL;
}
