sypodlobjects.h

这是一个基于COM的数据库访问技术

// SypODLObjects.h: interface for the CSypODLObjects class.
//
//////////////////////////////////////////////////////////////////////
//
// CSypODLObjects are set of classes that provide a very rich, 
// sophisticated, and user-friendly wrappers around ATL consumer 
// templates for OLEDB. These classes provide a lot of flexibility and
// functionality over OLEDB templates without loosing their power and  
// performance
//
// Author: G. Naik, [e-mail] (or [e-mail])
// You may freely use these classes in non-commercial products.These
// library is not to be sold for profit. 
//
// NOTE : Prior permission required by Sypram Technology (www.sypram.com)
// if you want to use this library in commercial projects. Send me an email
// if that is the case.
//
// CopyRight(C)2001. Sypram Technology. WWW.SYPRAM.COM
// Version : 1.0
//////////////////////////////////////////////////////////////////////

#if !defined(SYPOLEDB_DEFINED)
#define SYPOLEDB_DEFINED

#include "SypODLResource.h"

#include <comdef.h>
#include <atlbase.h>
#include <atldbcli.h>
#include <oledb.h>
#include <OleDBErr.h>

#include<adoid.h>
#include<adoint.h>

#define SYPODL_COMMANDTYPE_TABLE	1
#define SYPODL_COMMANDTYPE_QUERY	2
#define SYPODL_COMMANDTYPE_STORED	2

#define SYPODL_RECORDSETTYPE_FORWARDONLY 1

//******* GENERIC FUNCTIONS ***********

DATE DateFromDBTS(DBTIMESTAMP dbts);
DBTIMESTAMP DBTSFromDate(DATE dtSrc);
DBDATE DBDateFromDBTS(DBTIMESTAMP dtSrc);
DBTIMESTAMP DBTSFromDBDate(DBDATE mDDRet);
DBTIME DBTimeFromDBTS(DBTIMESTAMP dtSrc);
DBTIMESTAMP DBTSFromDBTime(DBTIME mDDRet);
LPCTSTR GetDataTypeName(WORD dbtype);

//****************************************************************************************

class  CSypODLException
{
	UINT    m_nCause;
	HRESULT m_nHr;
	CComPtr<IUnknown> m_pUnknown;

public:
	CSypODLException(UINT _m_cause, HRESULT hr=0, CComPtr<IUnknown> m_spUnk=0);
	void DisplayError();
	void GetError(CString&);
};

//****************************************************************************************

class CSypODLError
{
public:
	CSypODLError();
	virtual ~CSypODLError();

	CString	GetErrorCtx();
	CString	GetErrorLoc();
	CString	GetErrorMsg();
	void	ClearErrors();
protected:
	virtual void SetError(CString msg, CString loc, CString ctx);

	CString mErrCtx;
	CString mErrLoc;
	CString mErrMsg;
};

//****************************************************************************************

class  CSypODLConnection : public CSypODLError
{
private:
	CDataSource m_db;

	CString		m_Provider;
	CString		m_DSN;
	CString		m_UID;
	CString		m_PWD;
	HRESULT		hr;
	bool		m_bIsOpen;

public:
	CSession	m_session;
	bool	m_bEnableThrow;

public:
	CSypODLConnection();
	~CSypODLConnection();
	void SetProvider(CString);
	bool Open(CString m_DSN, CString m_UID, CString m_PWD);
	bool Open(CDBPropSet);
	bool IsOpen();
	void Close();
	bool StartTransaction(ISOLEVEL isoLevel=ISOLATIONLEVEL_READCOMMITTED, ULONG isoFlags=0);
	bool Abort(BOID	*pboidReason=NULL);
	bool Commit(BOOL bRetaining=FALSE, DWORD grfTC=XACTTC_SYNC, DWORD grfRM=0);
	bool Execute(CString sSQL);
};

//****************************************************************************************

const ULONG BUFFERSIZE = 5000;

template <typename TAccessor, typename TRowset=CRowset>
class  CSypODLRecordBase : public CSypODLError
{
    friend class CSypODLConnection;

protected:
	bool m_bIsOpen;
	UINT m_nRowsetType;
	HRESULT hr;
	bool m_bEOF, m_bBOF;
	bool m_bHasClientCursor;
	CAccessorRowset<TAccessor, TRowset> *m_pSet;

	DBCOLUMNINFO *m_pColsInfo;
	ULONG	m_nColCount;
	LPOLESTR m_pStrBuffer;
	CBookmark<4> m_BK;

public:
	bool m_bEnableThrow;

public:


	//===============================================================================

	CSypODLRecordBase()
	{
		m_pColsInfo = 0;
		m_pStrBuffer = 0;
		m_nColCount = 0;
		m_pSet = 0;
		m_bEnableThrow = true;
		m_bIsOpen = false;
		m_nRowsetType = 0;
		m_bEOF = false;
		m_bBOF = false;
		m_bHasClientCursor = true;
	}

	//===============================================================================

	bool IsEOF()
	{
		//=== Check if recordset is open
		if(!m_bIsOpen)
		{
			ThrowError(IDS_SYPODL_ERR_RECORDSETNOTOPEN);
			return false;
		}

		return m_bEOF;
	}

	//===============================================================================

	bool IsBOF()
	{
		//=== Check if recordset is open
		if(!m_bIsOpen)
		{
			ThrowError(IDS_SYPODL_ERR_RECORDSETNOTOPEN);
			return false;
		}

		return m_bBOF;
	}

	//===============================================================================
	virtual ~CSypODLRecordBase()
	{
	   if (m_pColsInfo != 0)
		  CoTaskMemFree(m_pColsInfo);

	   if (m_pStrBuffer != 0)
		  CoTaskMemFree(m_pStrBuffer);

	   Close();

	   if(m_pSet != 0)
		   delete m_pSet;
	}

	//===============================================================================

	TAccessor *GetAccessor()
	{
		return (TAccessor *) m_pSet;
	}

	//===============================================================================

	bool IsOpen()
	{
		return m_bIsOpen;
	}

	//===============================================================================

	void Close()
	{
		if(m_bIsOpen)
		{
			m_pSet->Close();
			m_bIsOpen = false;
			m_bEOF = false;
			m_bBOF = false;
		}
	}

	//===============================================================================

	virtual bool Open(CString sCommand, CSypODLConnection *pCnn, UINT nCommandType=2, UINT nRecordsetType=0)
	{
		Close(); // Close recordset if already open

		//=== Check if database is open
		if(!pCnn->IsOpen())
		{
			throw CSypODLException(IDS_SYPODL_ERR_DBNOTOPEN, 0);
			return false;
		}

		//=== Allocate buffer if not already done so
		if(m_pSet == 0)
		{
			if(nCommandType == 2)
				m_pSet = new CCommand<TAccessor, TRowset>;
			else
				m_pSet = new CTable<TAccessor, TRowset>;
		}

		CDBPropSet	propset(DBPROPSET_ROWSET);

		if(nRecordsetType != SYPODL_RECORDSETTYPE_FORWARDONLY)
			propset.AddProperty(DBPROP_IRowsetScroll, true);

		if(m_bHasClientCursor)
			propset.AddProperty(DBPROP_CLIENTCURSOR, true);

		propset.AddProperty(DBPROP_IRowsetChange, true);
		propset.AddProperty(DBPROP_UPDATABILITY, DBPROPVAL_UP_CHANGE | DBPROPVAL_UP_INSERT | DBPROPVAL_UP_DELETE);

		//=== Make sure that same type of recordset is opened repetitively
		if(m_nRowsetType != 0 && m_nRowsetType != nCommandType)
		{
			ThrowError(IDS_SYPODL_ERR_INVALIDCHANGETYPE, 0);
			return false;
		}

		//=== Open appropriate recordset type
		if(nCommandType == 2)
		{
			hr = ((CCommand<TAccessor, TRowset> *)m_pSet)->Open(pCnn->m_session, sCommand, &propset);
			m_nRowsetType = 2;
		}
		else
		{
			hr = ((CTable<TAccessor, TRowset> *)m_pSet)->Open(pCnn->m_session, sCommand, &propset);
			m_nRowsetType = 1;
		}

		//=== Process result
		if(FAILED(hr))
		{
			ThrowError(IDS_SYPODL_ERR_OPENRECORDSET, hr);
			return false;
		}

		//=== Populate column info structure
		hr = m_pSet->GetColumnInfo(&m_nColCount, &m_pColsInfo, &m_pStrBuffer);
		if(FAILED(hr))
		{
			ThrowError(IDS_SYPODL_ERR_GETROWCOUNT, hr);
			return false;
		}

		//=== Move recordset to the first record
		MoveToFirstRecord();

		m_bIsOpen = true;
		return true;
	}

	//===============================================================================

	virtual bool Open(CDBPropSet *propset, CString sCommand, CSypODLConnection *pCnn, UINT nCommandType=2)
	{
		Close(); // Close recordset if already open

		//=== Check if database is open
		if(!pCnn->IsOpen())
		{
			throw CSypODLException(IDS_SYPODL_ERR_DBNOTOPEN, 0);
			return false;
		}

		//=== Allocate buffer if not already done so
		if(m_pSet == 0)
		{
			if(nCommandType == 2)
				m_pSet = new CCommand<TAccessor, TRowset >;
			else
				m_pSet = new CTable<TAccessor, TRowset >;
		}

		//=== Make sure that same type of recordset is opened repetitively
		if(m_nRowsetType != 0 && m_nRowsetType != nCommandType)
		{
			ThrowError(IDS_SYPODL_ERR_INVALIDCHANGETYPE, 0);
			return false;
		}

		//=== Open appropriate recordset type
		if(nCommandType == 2)
		{
			hr = ((CCommand<TAccessor, TRowset> *)m_pSet)->Open(pCnn->m_session, sCommand, propset);
			m_nRowsetType = 2;
		}
		else
		{
			hr = ((CTable<TAccessor, TRowset> *)m_pSet)->Open(pCnn->m_session, sCommand, propset);
			m_nRowsetType = 1;
		}

		//=== Process result
		if(FAILED(hr))
		{
			ThrowError(IDS_SYPODL_ERR_OPENRECORDSET, hr);
			return false;
		}

		//=== Populate column info structure
		hr = m_pSet->GetColumnInfo(&m_nColCount, &m_pColsInfo, &m_pStrBuffer);
		if(FAILED(hr))
		{
			ThrowError(IDS_SYPODL_ERR_GETROWCOUNT, hr);
			return false;
		}

		//=== Move recordset to the first record
		MoveToFirstRecord();

		m_bIsOpen = true;
		return true;
	}

	//===============================================================================

	bool Insert()
	{
		if(!m_bIsOpen)
		{
			ThrowError(IDS_SYPODL_ERR_RECORDSETNOTOPEN);
			return false;
		}

		hr = m_pSet->Insert();

		if(FAILED(hr))
		{
			ThrowError(IDS_SYPODL_ERR_INSERTRECORD, hr);
			return false;
		}

		return true;
	}

	//===============================================================================

	bool SetData()
	{
		if(!m_bIsOpen)
		{
			ThrowError(IDS_SYPODL_ERR_RECORDSETNOTOPEN);
			return false;
		}

		hr = m_pSet->SetData();

		if(FAILED(hr))
		{
			ThrowError(IDS_SYPODL_ERR_EDITRECORD, hr);
			return false;
		}

		return true;
	}

	//===============================================================================

	bool Delete()
	{
		if(!m_bIsOpen)
		{
			ThrowError(IDS_SYPODL_ERR_RECORDSETNOTOPEN);
			return false;
		}