RE: long raw length

From: Enrico Mambrucchi <emambrucchi_at_seldat.it>
Date: Thu, 23 Mar 2000 08:44:21 +0100
Message-ID: <8bci25$g8e$1@serv1.iunet.it>

Hi
 Well, the length of a long raw field should be this, if you use ORADC component:

METHOD FieldSize
Applies To
OraField
Description
Returns the number of bytes stored in a LONG or LONG RAW field. Not available at design time and read-only at run time. Usage
data_size = orafield.FieldSize( )
data_size = orafield.DbFieldSize( )
Remarks
Returns the number of bytes stored in a LONG or LONG RAW field, up to a value of around 64KB. If the field contains more than 64KB, FieldSize returns -1 (negative one).
Oracle does not return the length of columns that are greater than 64KB, so the only way to determine the length is to retrieve the column. To conserve resources, columns of length greater than 64KB are not retrieved automatically.
Data Type
Long Integer

Then I tried with these function to transfer RTF files to DB and DB to RTF files.
It seems to work even if sometime if could happen some invalid character in the document, especially with long ones

Public Function DBtoFile(ByVal sFileName As String, ss As ADODB.Recordset, ByVal sFieldName As String, bNew As Boolean, Modello As String) As Boolean

    Dim hFile As Integer
    Dim lOffset As Long
    Dim vRTF As Variant
    Dim FILE_PORTION As Variant
    Dim LEN_BUFFER As Variant
    FILE_PORTION = &H7E00&
    LEN_BUFFER = 100000 ' 512
On Error GoTo errDBtoFile

    If sFileName = "" Then Exit Function     If sFieldName = "" Then Exit Function

    ' verifichiamo se abbiamo un cursore aperto, altrimenti simao nel caso di un

    ' nuovo record e quindi dobbiamo creare un file vuoto     If (ss Is Nothing) Then

        hFile = FreeFile
        Open sFileName For Output As hFile
        Close hFile
        bNew = True
    Else
        If Not ss.EOF Then
            If Not IsNull(ss.Fields(sFieldName).Value) Then
                lOffset = 100
                On Error Resume Next
                ss.Update
                On Error GoTo errDBtoFile
                hFile = FreeFile
                Open sFileName For Output As hFile
                Do
                    vRTF = ss.Fields(sFieldName).GetChunk(FILE_PORTION)
'lOffset
                    If IsNull(vRTF) Then vRTF = ""
                    vRTF = CStr(vRTF)
                    If vRTF <> "" Then Print #hFile, vRTF
                Loop Until vRTF = ""
                Close hFile
                bNew = False
            Else
                hFile = FreeFile
                FileCopy Modello, sFileName
                bNew = True
            End If
        Else
            hFile = FreeFile
            FileCopy Modello, sFileName
            bNew = True
        End If

    End If

    DBtoFile = True

fineDBtoFile:

    Exit Function

errDBtoFile:

    Resume fineDBtoFile
End Function

/

Function FileToDB (Source As String, T As ADODB.Recordset, _

      sField As String) As Boolean
          Dim NumBlocks As Integer, SourceFile As Integer, I As Integer
          Dim FileLength As Long, LeftOver As Long
          Dim FileData As String
          Dim RetVal As Variant
          Const BlockSize = 100000

          On Error GoTo Err_ReadBLOB

          ' Open the source file.
          SourceFile = FreeFile
          Open Source For Binary Access Read As SourceFile

          ' Get the length of the file.
          FileLength = LOF(SourceFile)
          If FileLength = 0 Then
              ReadBLOB = 0
              Exit Function
          End If

          ' Calculate the number of blocks to read and leftover bytes.
          T.Update
          NumBlocks = FileLength \ BlockSize
          LeftOver = FileLength Mod BlockSize

          ' Put first record in edit mode.
          ' Read the leftover data, writing it to the table.
          FileData = String$(LeftOver, 32)
          Get SourceFile, , FileData
          T.Fields(sField).AppendChunk (FileData)
          ' Read the remaining blocks of data, writing them to the table.
          FileData = String$(BlockSize, 32)
          For I = 1 To NumBlocks
              Get SourceFile, , FileData
              T.Fields(sField).AppendChunk (FileData)
          Next I
          ' Update the record and terminate function.
          T.Update
          Close SourceFile
          ReadBLOB = True
          Exit Function

Err_ReadBLOB:
          ReadBLOB = False
          Exit Function

End Function

I hope that this could be useful...

Bye
Enrico Mambrucchi
emambrucchi_at_seldat.it

Prakash <venkatprakash_at_hotmail.com> wrote in message 8ar8u0$us1$1_at_nnrp1.deja.com...
> Can anyone tell me how I do chunk long raw data? Also how do I know
> the length of a long raw column?
>
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.
Received on Thu Mar 23 2000 - 01:44:21 CST