Long data and SQLPutData ?

Long data and SQLPutData ?

am 08.08.2007 00:40:37 von Lothar Behrens

Hi,

I need some advice how to update a BLOB column. Reading it with
SQLGetData seems to be easier :-)

Do I need the commented code to 'shift' the bigger memory block into
the bound buffer while calling
SQLParamData and SQLPutData ?

I do set multiple column data before I do a SQLSetPos. So I have bound
columns therefore.
Do I get trouble, when I update some BLOB columns in between ?

Are there other issues with that code ?

Thanks, Lothar

Here I have code developed yet:

lbErrCodes LB_STDCALL lbQuery::setBinaryData(int column,
lb_I_BinaryData* value) {
// Declare a binary buffer to send 5000 bytes of data at a time.
SQLCHAR BinaryPtr[5000];
SQLINTEGER longDataLen;
SQLRETURN rc, retcode;

// The size may be more than 5000
longDataLen = SQL_LEN_DATA_AT_EXEC(value->getSize());

rc = SQLBindCol(hstmt, column, SQL_C_BINARY, (void *)BinaryPtr, 0,
&longDataLen);

retcode = SQLSetPos(hstmt, 1, SQL_UPDATE, SQL_LOCK_NO_CHANGE);

if (retcode == SQL_NEED_DATA)
{
retcode = SQLParamData(hstmt, (void **) &BinaryPtr);
while(retcode == SQL_NEED_DATA)
{

/*
//This code should be here to 'shift' the
datapieces.

void* peace = value->getNextDataPiece(5000);
long len = value->getCurrentPieceSize();
memcpy(BinaryPtr, piece, len);

*/

retcode = SQLPutData(hstmt, BinaryPtr, SQL_NTS);
/* check for error here */
retcode = SQLParamData(hstmt, (void **) &BinaryPtr);
}

}

return ERR_NONE;
}


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