greenplumn CMDKey 代码
文件路径：/src/backend/gporca/libgpopt/include/gpopt/mdcache/CMDKey.h
/---------------------------------------------------------------------------
/ Greenplum Database
/ Copyright (C) 2011 EMC Corp.
/
/ @filename:
/ CMDKey.h
/
/ @doc:
/ Key for metadata objects in the cache
/---------------------------------------------------------------------------
#ifndef GPOPT_CMDKey_H
#define GPOPT_CMDKey_H
#include "gpos/base.h"
#include "gpos/string/CWStringConst.h"
#include "naucrates/md/IMDId.h"
namespace gpopt
{
using namespace gpos;
using namespace gpmd;
/---------------------------------------------------------------------------
/ @class:
/ CMDKey
/
/ @doc:
/ Key for metadata objects in the cache
/
/---------------------------------------------------------------------------
class CMDKey
{
private:
/ id of the object in the underlying source
const IMDId *m_mdid;
public:
/ ctors
explicit CMDKey(const IMDId *mdid);
/ dtor
~CMDKey() = default;
const IMDId *
MDId() const
{
return m_mdid;
}
/ equality function
BOOL Equals(const CMDKey &mdkey) const;
/ hash function
ULONG HashValue() const;
/ equality function for using MD keys in a cache
static BOOL FEqualMDKey(CMDKey *const &pvLeft, CMDKey *const &pvRight);
/ hash function for using MD keys in a cache
static ULONG UlHashMDKey(CMDKey *const &pv);
};
} / namespace gpopt
#endif / !GPOPT_CMDKey_H
/ EOF