greenplumn CXformExpandNAryJoin 代码
文件路径：/src/backend/gporca/libgpopt/include/gpopt/xforms/CXformExpandNAryJoin.h
/---------------------------------------------------------------------------
/ Greenplum Database
/ Copyright (C) 2011 EMC Corp.
/
/ @filename:
/ CXformExpandNAryJoin.h
/
/ @doc:
/ Expand n-ary join into series of binary joins
/---------------------------------------------------------------------------
#ifndef GPOPT_CXformExpandNAryJoin_H
#define GPOPT_CXformExpandNAryJoin_H
#include "gpos/base.h"
#include "gpopt/xforms/CXformExploration.h"
namespace gpopt
{
using namespace gpos;
/---------------------------------------------------------------------------
/ @class:
/ CXformExpandNAryJoin
/
/ @doc:
/ Expand n-ary join into series of binary joins
/
/---------------------------------------------------------------------------
class CXformExpandNAryJoin : public CXformExploration
{
private:
public:
CXformExpandNAryJoin(const CXformExpandNAryJoin &) = delete;
/ ctor
explicit CXformExpandNAryJoin(CMemoryPool *mp);
/ dtor
~CXformExpandNAryJoin() override = default;
/ ident accessors
EXformId
Exfid() const override
{
return ExfExpandNAryJoin;
}
/ return a string for xform name
const CHAR *
SzId() const override
{
return "CXformExpandNAryJoin";
}
/ compute xform promise for a given expression handle
EXformPromise Exfp(CExpressionHandle &exprhdl) const override;
/ actual transform
void Transform(CXformContext *pxfctxt, CXformResult *pxfres,
CExpression *pexpr) const override;
}; / class CXformExpandNAryJoin
} / namespace gpopt
#endif / !GPOPT_CXformExpandNAryJoin_H
/ EOF
相关信息
相关文章
greenplumn CJoinOrderGreedy 源码
greenplumn CJoinOrderMinCard 源码
greenplumn CSubqueryHandler 源码