greenplumn CXformImplementSequenceProject 代码
文件路径：/src/backend/gporca/libgpopt/include/gpopt/xforms/CXformImplementSequenceProject.h
/---------------------------------------------------------------------------
/ Greenplum Database
/ Copyright (C) 2012 EMC Corp.
/
/ @filename:
/ CXformImplementSequenceProject.h
/
/ @doc:
/ Transform Logical Sequence Project to Physical Sequence Project
/---------------------------------------------------------------------------
#ifndef GPOPT_CXformImplementSequenceProject_H
#define GPOPT_CXformImplementSequenceProject_H
#include "gpos/base.h"
#include "gpopt/operators/CExpressionHandle.h"
#include "gpopt/xforms/CXformImplementation.h"
namespace gpopt
{
using namespace gpos;
/---------------------------------------------------------------------------
/ @class:
/ CXformImplementSequenceProject
/
/ @doc:
/ Transform Project to ComputeScalar
/
/---------------------------------------------------------------------------
class CXformImplementSequenceProject : public CXformImplementation
{
private:
public:
CXformImplementSequenceProject(const CXformImplementSequenceProject &) =
delete;
/ ctor
explicit CXformImplementSequenceProject(CMemoryPool *mp);
/ dtor
~CXformImplementSequenceProject() override = default;
/ ident accessors
EXformId
Exfid() const override
{
return ExfImplementSequenceProject;
}
const CHAR *
SzId() const override
{
return "CXformImplementSequenceProject";
}
/ compute xform promise for a given expression handle
EXformPromise
Exfp(CExpressionHandle &exprhdl) const override
{
if (exprhdl.DeriveHasSubquery(1))
{
return CXform::ExfpNone;
}
return CXform::ExfpHigh;
}
/ actual transform
void Transform(CXformContext *, CXformResult *,
CExpression *) const override;
}; / class CXformImplementSequenceProject
} / namespace gpopt
#endif / !GPOPT_CXformImplementSequenceProject_H
/ EOF
相关信息
相关文章
greenplumn CJoinOrderGreedy 源码
greenplumn CJoinOrderMinCard 源码
greenplumn CSubqueryHandler 源码