greenplumn CMDIdColStats 源码
greenplumn CMDIdColStats 代码
文件路径：/src/backend/gporca/libnaucrates/include/naucrates/md/CMDIdColStats.h
//---------------------------------------------------------------------------
// Greenplum Database
// Copyright (C) 2012 EMC Corp.
//
// @filename:
// CMDIdColStats.h
//
// @doc:
// Class for representing mdids for column statistics
//---------------------------------------------------------------------------
#ifndef GPMD_CMDIdColStats_H
#define GPMD_CMDIdColStats_H
#include "gpos/base.h"
#include "gpos/common/CDynamicPtrArray.h"
#include "gpos/string/CWStringConst.h"
#include "naucrates/dxl/gpdb_types.h"
#include "naucrates/md/CMDIdGPDB.h"
#include "naucrates/md/CSystemId.h"
namespace gpmd
{
using namespace gpos;
//---------------------------------------------------------------------------
// @class:
// CMDIdColStats
//
// @doc:
// Class for representing ids of column stats objects
//
//---------------------------------------------------------------------------
class CMDIdColStats : public IMDId
{
private:
// mdid of base relation
CMDIdGPDB *m_rel_mdid;
// position of the attribute in the base relation
ULONG m_attr_pos;
// buffer for the serialized mdid
WCHAR m_mdid_buffer[GPDXL_MDID_LENGTH];
// string representation of the mdid
CWStringStatic m_str;
// serialize mdid
void Serialize();
public:
CMDIdColStats(const CMDIdColStats &) = delete;
// ctor
CMDIdColStats(CMDIdGPDB *rel_mdid, ULONG attno);
// dtor
~CMDIdColStats() override;
EMDIdType
MdidType() const override
{
return EmdidColStats;
}
// string representation of mdid
const WCHAR *GetBuffer() const override;
// source system id
CSystemId
Sysid() const override
{
return m_rel_mdid->Sysid();
}
// accessors
IMDId *GetRelMdId() const;
ULONG Position() const;
// equality check
BOOL Equals(const IMDId *mdid) const override;
// computes the hash value for the metadata id
ULONG
HashValue() const override
{
return gpos::CombineHashes(m_rel_mdid->HashValue(),
gpos::HashValue(&m_attr_pos));
}
// is the mdid valid
BOOL
IsValid() const override
{
return IMDId::IsValid(m_rel_mdid);
}
// serialize mdid in DXL as the value of the specified attribute
void Serialize(CXMLSerializer *xml_serializer,
const CWStringConst *attribute_str) const override;
// debug print of the metadata id
IOstream &OsPrint(IOstream &os) const override;
// const converter
static const CMDIdColStats *
CastMdid(const IMDId *mdid)
{
GPOS_ASSERT(nullptr != mdid && EmdidColStats == mdid->MdidType());
return dynamic_cast<const CMDIdColStats *>(mdid);
}
// non-const converter
static CMDIdColStats *
CastMdid(IMDId *mdid)
{
GPOS_ASSERT(nullptr != mdid && EmdidColStats == mdid->MdidType());
return dynamic_cast<CMDIdColStats *>(mdid);
}
// make a copy in the given memory pool
IMDId *
Copy(CMemoryPool *mp) const override
{
CMDIdGPDB *mdid_rel = CMDIdGPDB::CastMdid(m_rel_mdid->Copy(mp));
return GPOS_NEW(mp) CMDIdColStats(mdid_rel, m_attr_pos);
}
};
} // namespace gpmd
#endif // !GPMD_CMDIdColStats_H
// EOF
相关信息
相关文章
greenplumn CDXLStatsDerivedColumn 源码
greenplumn CDXLStatsDerivedRelation 源码
greenplumn CMDAggregateGPDB 源码
0
赞
热门推荐
-
2、 - 优质文章
-
3、 gate.io
-
8、 golang
-
9、 openharmony
-
10、 Vue中input框自动聚焦