sqldata.cpp

以OLE DB风格访问DB2数据库的C++类源码

			ASSERT(m_pData->nBufferSize >= sizeof(TIMESTAMP_STRUCT));
			TIMESTAMP_STRUCT* pData = (TIMESTAMP_STRUCT*) GetBuffer();
			::sscanf(pszValue, "%d-%d-%d %d:%d:%d.%d",
				&pData->year, &pData->month, &pData->day,
				&pData->hour, &pData->minute, &pData->second,
				&pData->fraction);
			if (!m_pData->nScale)
				pData->fraction = 0;
		}
		m_pData->nIndicator = sizeof(TIMESTAMP_STRUCT);
		break;
	default:
		return SetValue(pszValue);
	}
	return TRUE;
}

// Converts the value to string
int CSqlVariant::ToString(std::string& strValue)
{
	strValue.resize(0);
	if (IsNull())
		return 0;

	int nSize = GetDisplaySize();
	if (nSize <= 0)
		return 0;

	strValue.resize(nSize+1);
	char* pszBuff = &strValue[0];

	switch (m_pData->nDataType)
	{
	case SQL_C_SHORT:
		::itoa((int)m_pData->iVal, pszBuff, 10);
		break;
	case SQL_C_LONG:
		::itoa(m_pData->nVal, pszBuff, 10);
		break;
	case SQL_C_SBIGINT:
#if defined(__xlC__) || defined(__IBMC__) || defined(__IBMCPP__)
		::lltoa(m_pData->lVal, pszBuff, 10);
#else
		::_i64toa(m_pData->lVal, pszBuff, 10);
#endif
		break;
	case SQL_C_FLOAT:
		::sprintf(pszBuff, "%*f", m_pData->fltVal);
		break;
	case SQL_C_DOUBLE:
		::sprintf(pszBuff, "%*lf", m_pData->dbVal);
		break;
	case SQL_C_TYPE_DATE:
		::sprintf(pszBuff, "%d-%02d-%02d", m_pData->dtVal.year,
			m_pData->dtVal.month, m_pData->dtVal.day);
		break;
	case SQL_C_TYPE_TIME:
		::sprintf(pszBuff, "%02d:%02d:%02d", m_pData->tmVal.hour,
			m_pData->tmVal.minute, m_pData->tmVal.second);
		break;
	case SQL_C_TYPE_TIMESTAMP:
		{
			const TIMESTAMP_STRUCT* pData = GetTimeStamp();
			::sprintf(pszBuff, "%d-%d-%d %d:%d:%d.%d",
				pData->year, pData->month, pData->day,
				pData->hour, pData->minute, pData->second,
				pData->fraction);
		}
		break;
	default:
		::memcpy(pszBuff, m_pData->pVal, nSize);
		pszBuff[nSize] = 0;
		// remove the trailing spaces, added May 20, 2002
		nSize = (int)::strlen(pszBuff);
		while (nSize > 0 && pszBuff[nSize-1] == ' ')
			nSize--;
		pszBuff[nSize] = 0;
		break;
	}

	//strValue.resize(string::traits_type::length(strValue.c_str()));
	strValue.resize(::strlen(strValue.c_str()));
	return (int)strValue.size();
}


//////////////////////////////////////////////////////////////////////
// class CSqlParameter - Represents a parameter or argument
// associated with a SQL statement or stored procedure
//////////////////////////////////////////////////////////////////////

CSqlParameter::CSqlParameter() :
	m_bBindFile(FALSE),
	m_nFileOptions(SQL_FILE_READ),
	m_nSqlType(SQL_UNKNOWN_TYPE),
	m_nIoType(SQL_PARAM_INPUT)		// SQL_PARAM_TYPE_UNKNOWN
{
}

CSqlParameter::CSqlParameter(const CSqlParameter& rData)
{
	*this = rData;
}

CSqlParameter::~CSqlParameter()
{
}

// Initializes a parameter
// Arguments:
//	nSqlType - Specifies the SQL data type of the parameter.
//	nIoType - Specifies the input/output type of the parameter.
//	nPrecision - Specifies the precision of the parameter.
//		- For a binary or single byte string, it is in unit of byte
//		- For a double byte string, it is in unit of double-byte
//		- For NUMERIC or DECIMAL, it is the decimal precision.
//		- For fixed-length data type, this argument is ignored
//	nScale - Specifies the scale if nSqlType is SQL_NUMERIC, SQL_ECIMAL, or SQL_TIMESTAMP
BOOL CSqlParameter::CreateParameter(SQLSMALLINT nSqlType, SQLSMALLINT nIoType,
									SQLUINTEGER nPrecision, SQLSMALLINT nScale)
{
	if (!CreateBuffer(nSqlType, nPrecision))
		return FALSE;

	m_pData->nScale = nScale;
	m_nIoType = nIoType;
	m_bBindFile = FALSE;
	return TRUE;
}

// Initializes a file-binding parameter
// Arguments:
//	nSqlType - Specifies the SQL data type of the parameter. It can only be BLOB, CLOB, or DBCLOB.
BOOL CSqlParameter::CreateFileParam(SQLSMALLINT nSqlType)
{
	if (!AllocBuffer(MAX_PATH))
		return FALSE;

	m_pData->nDataType = SQL_C_CHAR;
	m_pData->nSqlType = SQL_CHAR;
	ASSERT(nSqlType == SQL_BLOB ||
		nSqlType == SQL_CLOB ||
		nSqlType == SQL_DBCLOB);
	m_nSqlType = nSqlType;
	m_bBindFile = TRUE;
	return TRUE;
}

// Binds the parameter to a command object
// This function should be called before SQLExecute()
BOOL CSqlParameter::Bind(CSqlCommand* pStmt, int nOrdinal)
{
	SQLRETURN nRet;
	ASSERT(pStmt != NULL);
	ASSERT(pStmt->IsOpen());
	if (!m_bBindFile)
	{
		nRet = ::SQLBindParameter(pStmt->GetHandle(), nOrdinal, m_nIoType,
			m_pData->nDataType, m_pData->nSqlType, m_pData->nPrecision, m_pData->nScale,
			(SQLPOINTER) (IsDefault() ? NULL : m_pData->pVal),
			GetMaxSize(), &m_pData->nIndicator);
	}
	else
	{
		ASSERT(!IsDefault());
		m_pData->nIndicator = 0;	// must be set to 0
		nRet = ::SQLBindFileToParam(pStmt->GetHandle(), nOrdinal, m_nSqlType,
			GetBuffer(), NULL, &m_nFileOptions, (SQLSMALLINT)GetMaxSize(), &m_pData->nIndicator);
	}
	return pStmt->SqlCheck(nRet);
}

// Unbinds the parameter
BOOL CSqlParameter::Unbind(CSqlCommand* pStmt, int nOrdinal)
{
	BOOL bOK = CSqlVariant::Unbind(pStmt, nOrdinal);
	if (bOK && pStmt != NULL && pStmt->IsOpen() && !m_bBindFile)
		bOK = pStmt->SqlCheck(::SQLBindParameter(pStmt->GetHandle(), nOrdinal,
			0, SQL_C_DEFAULT, SQL_DEFAULT, 0, 0, NULL, 0, NULL));
	return bOK;
}

CSqlParameter& CSqlParameter::operator=(const CSqlParameter& rValue)
{
	if (this != &rValue)
	{
		CopyData(rValue);
		m_bBindFile = rValue.m_bBindFile;
		m_nFileOptions = rValue.m_nFileOptions;
		m_nSqlType = rValue.m_nSqlType;
		m_nIoType = rValue.m_nIoType;
	}
	return *this;
}


//////////////////////////////////////////////////////////////////////
// class CSqlField - Represents a column of data in a recordset
//////////////////////////////////////////////////////////////////////

CSqlField::CSqlField() :
	m_bBindFile(FALSE),
	m_nFileOptions(SQL_FILE_OVERWRITE),
	m_nOrdinal(0),
	m_bNullable(FALSE)
{
}

CSqlField::CSqlField(const CSqlField& rData)
{
	*this = rData;
}

CSqlField::~CSqlField()
{
}

// Initializes a field object
// Application call this function when the column size and type is known
// and auto-binding is not wanted.
// Arguments:
//	pszFieldName - Specifies the column name. It can be an SQL expression
//	nDataType - Specifies the C data type of the field
//	nDataSize - Specifies the maximum length in bytes of the field.
//		This argument is ignored if nDataType specifies a fixed-length data type.
BOOL CSqlField::CreateField(PCSTR pszFieldName, SQLSMALLINT nDataType, SQLINTEGER nDataSize)
{
	for (int n=0; n<MAX_SQL_TYPE; n++)
		if (nDataType == m_tblDataType[n].nDataType)
			break;

	if (n < MAX_SQL_TYPE)	// it's a valid data type
	{
		if (m_tblDataType[n].nDataSize != 0)	// fixed-length data type
			nDataSize = m_tblDataType[n].nDataSize;
	}

	if (!AllocBuffer(nDataSize))
		return FALSE;

	m_pData->nDataType = nDataType;
	m_pData->nIndicator = 0;
	m_strName = pszFieldName;
	m_nOrdinal = 0;
	m_bBindFile = FALSE;
	return TRUE;
}

// Initializes a field according to the attribute of the specified column in a recordset.
BOOL CSqlField::CreateField(CSqlCommand* pStmt, int nOrdinal)
{
	// get the column information
	SQLCHAR szName[256];
	SQLSMALLINT nNameSize, nSqlType, nScale, nNullable;
	SQLUINTEGER nPrecision;

	if (!pStmt->SqlCheck(::SQLDescribeCol(pStmt->GetHandle(), nOrdinal, szName, sizeof(szName),
		&nNameSize, &nSqlType, &nPrecision, &nScale, &nNullable)))
		return FALSE;
	if (!CreateBuffer(nSqlType, nPrecision))
		return FALSE;

	// calls SQLColAttribute(SQL_DESC_UPDATABLE) to check if the column is updatable.
	// if the column should not be updated, places SQL_ROW_IGNORE in StrLen_or_IndPtr
	// buffer when SQLSetPos() for SQL_UPDATE is called.

	m_pData->nScale = nScale;
	m_strName.assign((const char*) szName);
	m_nOrdinal = nOrdinal;
	m_bBindFile = FALSE;
	m_bNullable = (SQL_NULLABLE == nNullable);
	return TRUE;
}

// Initializes a file-binding field
// Arguments:
//	pszFieldName - Specifies the column name.
//	nFileOption - Specifies the file access option.
//		SQL_FILE_CREATE - create a new file.
//		SQL_FILE_OVERWRITE - overwrite existing file, or create a new file
//		SQL_FILE_APPEND - append to existing file, or create a new file
BOOL CSqlField::CreateFileField(PCSTR pszFieldName, SQLUINTEGER nFileOption)
{
	if (!AllocBuffer(MAX_PATH))
		return FALSE;

	m_pData->nSqlType = SQL_CHAR;
	m_pData->nDataType = SQL_C_CHAR;
	m_pData->nIndicator = 0;
	m_nFileOptions = nFileOption;
	m_strName = pszFieldName;
	m_nOrdinal = 0;
	m_bBindFile = TRUE;
	return TRUE;
}

// Binds a field to a column in the recordset
BOOL CSqlField::Bind(CSqlCommand* pStmt, int nOrdinal)
{
	ASSERT(!IsDefault());
	ASSERT(pStmt != NULL);
	ASSERT(pStmt->IsOpen());

	m_pData->nIndicator = 0;
	if (m_nOrdinal != 0)
		nOrdinal = m_nOrdinal;
	SQLRETURN nRet;
	if (!m_bBindFile)
	{
		nRet = ::SQLBindCol(pStmt->GetHandle(), nOrdinal, m_pData->nDataType,
			GetBuffer(), GetMaxSize(), &m_pData->nIndicator);
	}
	else
	{
		nRet = ::SQLBindFileToCol(pStmt->GetHandle(), nOrdinal, GetBuffer(),
			NULL, &m_nFileOptions, (SQLSMALLINT)GetMaxSize(), NULL, &m_pData->nIndicator);
	}

	return pStmt->SqlCheck(nRet);
}

// Unbinds a field from the recordset
BOOL CSqlField::Unbind(CSqlCommand* pStmt, int nOrdinal)
{
	BOOL bOK = CSqlVariant::Unbind(pStmt, nOrdinal);
	if (bOK && pStmt != NULL && pStmt->IsOpen())
	{
		if (!m_bBindFile)
			bOK = pStmt->SqlCheck(::SQLBindCol(pStmt->GetHandle(), nOrdinal,
				SQL_C_DEFAULT, NULL, 0, NULL));
		else
			bOK = pStmt->SqlCheck(::SQLBindFileToCol(pStmt->GetHandle(), nOrdinal,
				NULL, NULL, NULL, 0, NULL, NULL));
	}

	return bOK;
}

CSqlField& CSqlField::operator=(const CSqlField& rValue)
{
	if (this != &rValue)
	{
		CopyData(rValue);
		m_bBindFile = rValue.m_bBindFile;
		m_nFileOptions = rValue.m_nFileOptions;
		m_strName = rValue.m_strName;
		m_bNullable = rValue.m_bNullable;
		m_nOrdinal = rValue.m_nOrdinal;
	}
	return *this;
}