Visual C++中使用OLE DB读写SQL Server简明指南

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读操作也完成了，是不是仍然很简单呢？下面我们再来看看最麻烦的二进制数据（text、ntext、image等）的读写。要实现BLOB数据的读写，我们需要一个辅助的类，定义如下：
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0sZ9?A!Vclass CSequentialStream : public ISequentialStream    // BLOB 数据访问类

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    virtual operator void* const( ) { return m_pBuffer; };
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HRESULT PreAllocBuffer( ULONG uSize );
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