greenplumn CXformIntersect2Join 代码
文件路径：/src/backend/gporca/libgpopt/src/xforms/CXformIntersect2Join.cpp
/---------------------------------------------------------------------------
/ Greenplum Database
/ Copyright (C) 2013 VMware, Inc. or its affiliates.
/
/ @filename:
/ CXformIntersect2Join.cpp
/
/ @doc:
/ Implement the transformation of Intersect into a Join
/---------------------------------------------------------------------------
#include "gpopt/xforms/CXformIntersect2Join.h"
#include "gpos/base.h"
#include "gpopt/base/CColRefComputed.h"
#include "gpopt/base/CUtils.h"
#include "gpopt/exception.h"
#include "gpopt/operators/CLogicalInnerJoin.h"
#include "gpopt/operators/CLogicalIntersect.h"
#include "gpopt/operators/COperator.h"
#include "gpopt/operators/CPatternLeaf.h"
#include "gpopt/operators/CScalarProjectList.h"
#include "gpopt/xforms/CXformUtils.h"
using namespace gpmd;
using namespace gpopt;
/---------------------------------------------------------------------------
/ @function:
/ CXformIntersect2Join::CXformIntersect2Join
/
/ @doc:
/ Ctor
/
/---------------------------------------------------------------------------
CXformIntersect2Join::CXformIntersect2Join(CMemoryPool *mp)
: CXformExploration(
/ pattern
GPOS_NEW(mp) CExpression(
mp, GPOS_NEW(mp) CLogicalIntersect(mp),
GPOS_NEW(mp) CExpression(
mp, GPOS_NEW(mp) CPatternLeaf(mp)), / left relational child
GPOS_NEW(mp) CExpression(
mp, GPOS_NEW(mp) CPatternLeaf(mp)) / right relational child
))
{
}
/---------------------------------------------------------------------------
/ @function:
/ CXformIntersect2Join::Transform
/
/ @doc:
/ Actual transformation that transforms an intersect into a join
/ over a group by over the inputs
/
/---------------------------------------------------------------------------
void
CXformIntersect2Join::Transform(CXformContext *pxfctxt, CXformResult *pxfres,
CExpression *pexpr) const
{
GPOS_ASSERT(nullptr != pxfctxt);
GPOS_ASSERT(nullptr != pxfres);
GPOS_ASSERT(FPromising(pxfctxt->Pmp(), this, pexpr));
GPOS_ASSERT(FCheckPattern(pexpr));
CMemoryPool *mp = pxfctxt->Pmp();
GPOS_ASSERT(2 == pexpr->Arity());
/ extract components
CExpression *pexprLeftChild = (*pexpr)[0];
CExpression *pexprRightChild = (*pexpr)[1];
CLogicalIntersect *popIntersect =
CLogicalIntersect::PopConvert(pexpr->Pop());
CColRef2dArray *pdrgpdrgpcrInput = popIntersect->PdrgpdrgpcrInput();
/ construct group by over the left and right expressions
CExpression *pexprProjList =
GPOS_NEW(mp) CExpression(mp, GPOS_NEW(mp) CScalarProjectList(mp),
GPOS_NEW(mp) CExpressionArray(mp));
pexprProjList->AddRef();
pexprLeftChild->AddRef();
pexprRightChild->AddRef();
(*pdrgpdrgpcrInput)[0]->AddRef();
(*pdrgpdrgpcrInput)[1]->AddRef();
CExpression *pexprLeftAgg = CUtils::PexprLogicalGbAggGlobal(
mp, (*pdrgpdrgpcrInput)[0], pexprLeftChild, pexprProjList);
CExpression *pexprRightAgg = CUtils::PexprLogicalGbAggGlobal(
mp, (*pdrgpdrgpcrInput)[1], pexprRightChild, pexprProjList);
CExpression *pexprScCond = CUtils::PexprConjINDFCond(mp, pdrgpdrgpcrInput);
CExpression *pexprJoin =
GPOS_NEW(mp) CExpression(mp, GPOS_NEW(mp) CLogicalInnerJoin(mp),
pexprLeftAgg, pexprRightAgg, pexprScCond);
pxfres->Add(pexprJoin);
}
/ EOF
相关信息
相关文章
greenplumn CJoinOrderGreedy 源码
greenplumn CJoinOrderMinCard 源码
greenplumn CSubqueryHandler 源码