//---------------------------------------------------------------------------
// @function:
// CXformDifferenceAll2LeftAntiSemiJoin::Transform
//
// @doc:
// Actual transformation
//
//---------------------------------------------------------------------------
void
CXformDifferenceAll2LeftAntiSemiJoin::Transform
(
CXformContext *pxfctxt,
CXformResult *pxfres,
CExpression *pexpr
)
const
{
GPOS_ASSERT(NULL != pxfctxt);
GPOS_ASSERT(FPromising(pxfctxt->Pmp(), this, pexpr));
GPOS_ASSERT(FCheckPattern(pexpr));
IMemoryPool *pmp = pxfctxt->Pmp();
// TODO: , Jan 8th 2013, we currently only handle difference all
// operators with two children
GPOS_ASSERT(2 == pexpr->UlArity());
// extract components
CExpression *pexprLeftChild = (*pexpr)[0];
CExpression *pexprRightChild = (*pexpr)[1];
CLogicalDifferenceAll *popDifferenceAll = CLogicalDifferenceAll::PopConvert(pexpr->Pop());
DrgDrgPcr *pdrgpdrgpcrInput = popDifferenceAll->PdrgpdrgpcrInput();
CExpression *pexprLeftWindow = CXformUtils::PexprWindowWithRowNumber(pmp, pexprLeftChild, (*pdrgpdrgpcrInput)[0]);
CExpression *pexprRightWindow = CXformUtils::PexprWindowWithRowNumber(pmp, pexprRightChild, (*pdrgpdrgpcrInput)[1]);
DrgDrgPcr *pdrgpdrgpcrInputNew = GPOS_NEW(pmp) DrgDrgPcr(pmp);
DrgPcr *pdrgpcrLeftNew = CUtils::PdrgpcrExactCopy(pmp, (*pdrgpdrgpcrInput)[0]);
pdrgpcrLeftNew->Append(CXformUtils::PcrProjectElement(pexprLeftWindow, 0 /* row_number window function*/));
DrgPcr *pdrgpcrRightNew = CUtils::PdrgpcrExactCopy(pmp, (*pdrgpdrgpcrInput)[1]);
pdrgpcrRightNew->Append(CXformUtils::PcrProjectElement(pexprRightWindow, 0 /* row_number window function*/));
pdrgpdrgpcrInputNew->Append(pdrgpcrLeftNew);
pdrgpdrgpcrInputNew->Append(pdrgpcrRightNew);
// generate the scalar condition for the left anti-semi join
CExpression *pexprScCond = CUtils::PexprConjINDFCond(pmp, pdrgpdrgpcrInputNew);
// assemble the new left anti-semi join logical operator
CExpression *pexprLASJ = GPOS_NEW(pmp) CExpression
(
pmp,
GPOS_NEW(pmp) CLogicalLeftAntiSemiJoin(pmp),
pexprLeftWindow,
pexprRightWindow,
pexprScCond
);
// clean up
pdrgpdrgpcrInputNew->Release();
// add alternative to results
pxfres->Add(pexprLASJ);
}
//---------------------------------------------------------------------------
// @function:
// CXformSelect2PartialDynamicIndexGet::CreatePartialIndexGetPlan
//
// @doc:
// Create a plan as a union of the given partial index get candidates and
// possibly a dynamic table scan
//
//---------------------------------------------------------------------------
void
CXformSelect2PartialDynamicIndexGet::CreatePartialIndexGetPlan
(
IMemoryPool *pmp,
CExpression *pexpr,
DrgPpartdig *pdrgppartdig,
const IMDRelation *pmdrel,
CXformResult *pxfres
)
const
{
CExpression *pexprRelational = (*pexpr)[0];
CExpression *pexprScalar = (*pexpr)[1];
CLogicalDynamicGet *popGet = CLogicalDynamicGet::PopConvert(pexprRelational->Pop());
DrgPcr *pdrgpcrGet = popGet->PdrgpcrOutput();
const ULONG ulPartialIndexes = pdrgppartdig->UlLength();
DrgDrgPcr *pdrgpdrgpcrInput = GPOS_NEW(pmp) DrgDrgPcr(pmp);
DrgPexpr *pdrgpexprInput = GPOS_NEW(pmp) DrgPexpr(pmp);
for (ULONG ul = 0; ul < ulPartialIndexes; ul++)
{
SPartDynamicIndexGetInfo *ppartdig = (*pdrgppartdig)[ul];
const IMDIndex *pmdindex = ppartdig->m_pmdindex;
CPartConstraint *ppartcnstr = ppartdig->m_ppartcnstr;
DrgPexpr *pdrgpexprIndex = ppartdig->m_pdrgpexprIndex;
DrgPexpr *pdrgpexprResidual = ppartdig->m_pdrgpexprResidual;
DrgPcr *pdrgpcrNew = pdrgpcrGet;
if (0 < ul)
{
pdrgpcrNew = CUtils::PdrgpcrCopy(pmp, pdrgpcrGet);
}
else
{
pdrgpcrNew->AddRef();
}
CExpression *pexprDynamicScan = NULL;
if (NULL != pmdindex)
{
pexprDynamicScan = CXformUtils::PexprPartialDynamicIndexGet
(
pmp,
popGet,
pexpr->Pop()->UlOpId(),
pdrgpexprIndex,
pdrgpexprResidual,
pdrgpcrNew,
pmdindex,
pmdrel,
ppartcnstr,
NULL, // pcrsAcceptedOuterRefs
NULL, // pdrgpcrOuter
NULL // pdrgpcrNewOuter
);
}
else
{
pexprDynamicScan = PexprSelectOverDynamicGet
(
pmp,
popGet,
pexprScalar,
pdrgpcrNew,
ppartcnstr
);
}
GPOS_ASSERT(NULL != pexprDynamicScan);
pdrgpdrgpcrInput->Append(pdrgpcrNew);
pdrgpexprInput->Append(pexprDynamicScan);
}
ULONG ulInput = pdrgpexprInput->UlLength();
if (0 < ulInput)
{
CExpression *pexprResult = NULL;
if (1 < ulInput)
{
pdrgpcrGet->AddRef();
DrgPcr *pdrgpcrOuter = pdrgpcrGet;
// construct a new union all operator
pexprResult = GPOS_NEW(pmp) CExpression
(
pmp,
GPOS_NEW(pmp) CLogicalUnionAll(pmp, pdrgpcrOuter, pdrgpdrgpcrInput, popGet->UlScanId()),
pdrgpexprInput
);
}
else
{
pexprResult = (*pdrgpexprInput)[0];
pexprResult->AddRef();
// clean up
pdrgpexprInput->Release();
pdrgpdrgpcrInput->Release();
}
// if scalar expression involves the partitioning key, keep a SELECT node
// on top for the purposes of partition selection
DrgDrgPcr *pdrgpdrgpcrPartKeys = popGet->PdrgpdrgpcrPart();
CExpression *pexprPredOnPartKey = CPredicateUtils::PexprExtractPredicatesOnPartKeys
(
pmp,
pexprScalar,
pdrgpdrgpcrPartKeys,
NULL, /*pcrsAllowedRefs*/
true /*fUseConstraints*/
);
if (NULL != pexprPredOnPartKey)
{
pexprResult = GPOS_NEW(pmp) CExpression(pmp, GPOS_NEW(pmp) CLogicalSelect(pmp), pexprResult, pexprPredOnPartKey);
}
pxfres->Add(pexprResult);
return;
}
// clean up
pdrgpdrgpcrInput->Release();
pdrgpexprInput->Release();
}
