qsqlcachedresult_p.h

来自「qt-x11-opensource-src-4.1.4.tar.gz源码」· C头文件 代码 · 共 78 行

/****************************************************************************
**
** Copyright (C) 1992-2006 Trolltech ASA. All rights reserved.
**
** This file is part of the QtSql module of the Qt Toolkit.
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** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file.  Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
** http://www.trolltech.com/products/qt/opensource.html
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** review the following information:
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** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
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#ifndef QSQLCACHEDRESULT_P_H
#define QSQLCACHEDRESULT_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists for the convenience
// of other Qt classes.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include "QtSql/qsqlresult.h"

class QVariant;
template <typename T> class QVector;

class QSqlCachedResultPrivate;

class Q_SQL_EXPORT QSqlCachedResult: public QSqlResult
{
public:
    virtual ~QSqlCachedResult();

    typedef QVector<QVariant> ValueCache;

protected:
    QSqlCachedResult(const QSqlDriver * db);

    void init(int colCount);
    void cleanup();
    void clearValues();

    virtual bool gotoNext(ValueCache &values, int index) = 0;

    QVariant data(int i);
    bool isNull(int i);
    bool fetch(int i);
    bool fetchNext();
    bool fetchPrevious();
    bool fetchFirst();
    bool fetchLast();

    int colCount() const;
    ValueCache &cache();

private:
    bool cacheNext();
    QSqlCachedResultPrivate *d;
};

#endif // QSQLCACHEDRESULT_P_H