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secondo/Algebras/TupleIdentifier/TupleIdentifier.h
2026-01-23 17:03:45 +08:00

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/*
----
This file is part of SECONDO.
Copyright (C) 2004, University in Hagen, Department of Computer Science,
Database Systems for New Applications.
SECONDO is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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(at your option) any later version.
SECONDO is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with SECONDO; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
----
//paragraph [1] title: [{\Large \bf ] [}]
[1] TupleIdentifier Algebra
March 2005 Matthias Zielke
The only purpose of this algebra is to provide a typeconstructor 'tid' so that the tupleidentifiers
of tuples from relations can be stored as attributvalues in different tuples. This feature is needed
for the implementation of operators to update relations.
1 Preliminaries
1.1 Includes
*/
#ifndef TUPLEIDENTIFIER_H
#define TUPLEIDENTIFIER_H
#include "Algebra.h"
#include "NestedList.h"
#include "ListUtils.h"
#include "QueryProcessor.h"
#include "StandardTypes.h"
#include <string>
extern NestedList* nl;
extern QueryProcessor *qp;
typedef SmiRecordId TupleId;
/*
2 Type Constructor ~tid~
2.1 Data Structure - Class ~TupleIdentifier~
*/
class TupleIdentifier: public Attribute
{
public:
TupleIdentifier( bool DEFINED, TupleId TID = 0 );
TupleIdentifier(const TupleIdentifier& source);
inline TupleIdentifier() {};
/*
This constructor should not be used.
*/
~TupleIdentifier();
TupleId GetTid() const;
void SetTid( const TupleId tid);
TupleIdentifier* Clone() const;
std::ostream& Print( std::ostream& os ) const;
inline void Set(const bool DEFINED, const TupleId ID)
{
SetDefined( DEFINED);
this->tid = static_cast<long>(ID);
}
inline size_t Sizeof() const
{
return sizeof( *this );
}
inline size_t HashValue() const
{
return (IsDefined() ? tid : 0);
}
void CopyFrom(const Attribute* right);
inline int Compare(const Attribute *arg) const
{
const TupleIdentifier* tupleI = (const TupleIdentifier*)(arg);
return Compare(*tupleI);
}
inline int Compare(const TupleIdentifier& t) const
{
bool argDefined = t.IsDefined();
if(!IsDefined() && !argDefined)
return 0;
if(!IsDefined())
return -1;
if(!argDefined)
return 1;
if ( tid < t.GetTid() )
return (-1);
if ( tid > t.GetTid())
return (1);
return (0);
}
bool Adjacent(const Attribute *arg) const;
static void* Cast(void* addr){
return new (addr) TupleIdentifier();
}
/*
Additional functions for integration in ~jlist~
*/
static ListExpr Out(ListExpr typeInfo, Word value);
static Word In(const ListExpr typeInfo, const ListExpr instance,
const int errorPos, ListExpr& errorInfo, bool& correct);
static bool Save(SmiRecord& valueRecord, size_t& offset,
const ListExpr typeInfo, Word& value );
static bool Open(SmiRecord& valueRecord, size_t& offset,
const ListExpr typeInfo, Word& value );
TupleIdentifier& operator=(const TupleIdentifier& other);
bool operator==(const TupleIdentifier& other) const;
/*
Basic Type
*/
static const std::string BasicType(){
return "tid";
}
static bool checkType(const ListExpr type){
return listutils::isSymbol(type, BasicType());
}
/*
Example String for external Property Files includin TupleIds
*/
static const std::string Example(){
return "50060";
}
private:
TupleId tid;
};
#endif