greenplumn CXformCollapseProject 源码
greenplumn CXformCollapseProject 代码
文件路径：/src/backend/gporca/libgpopt/include/gpopt/xforms/CXformCollapseProject.h
//---------------------------------------------------------------------------
// Greenplum Database
// Copyright (C) 2015 VMware, Inc. or its affiliates.
//
// @filename:
// CXformCollapseProject.h
//
// @doc:
// Transform that collapses two cascaded project nodes
//---------------------------------------------------------------------------
#ifndef GPOPT_CXformCollapseProject_H
#define GPOPT_CXformCollapseProject_H
#include "gpos/base.h"
#include "gpopt/xforms/CXformSubqueryUnnest.h"
namespace gpopt
{
using namespace gpos;
//---------------------------------------------------------------------------
// @class:
// CXformCollapseProject
//
// @doc:
// Transform that collapses two cascaded project nodes
//
//---------------------------------------------------------------------------
class CXformCollapseProject : public CXformExploration
{
private:
public:
CXformCollapseProject(const CXformCollapseProject &) = delete;
// ctor
explicit CXformCollapseProject(CMemoryPool *mp);
// dtor
~CXformCollapseProject() override = default;
// ident accessors
EXformId
Exfid() const override
{
return ExfCollapseProject;
}
// return a string for xform name
const CHAR *
SzId() const override
{
return "CXformCollapseProject";
}
// compute xform promise for a given expression handle
EXformPromise Exfp(CExpressionHandle &exprhdl) const override;
// actual transform
void Transform(CXformContext *, CXformResult *,
CExpression *) const override;
}; // class CXformCollapseProject
} // namespace gpopt
#endif // !GPOPT_CXformCollapseProject_H
// EOF
相关信息
相关文章
greenplumn CJoinOrderGreedy 源码
greenplumn CJoinOrderMinCard 源码
greenplumn CSubqueryHandler 源码
0
赞
热门推荐
-
2、 - 优质文章
-
3、 gate.io
-
6、 golang
-
8、 openharmony