Oracle ODBC and BLOB in html

Question

Hi,
I would like to ask you if cad I use Oracle-ODBC driver (whuch version) for reading BLOB (LRAW) column in html(asp) - JavaScript.
create table JPG
CLZM NUMBER(6) not null,
JPG_FILE LONG RAW null ,
<% @ LANGUAGE=JavaScript%>
<%
Response.Buffer = true;
Response.ContentType = "image/jpeg";
Response.AddHeader("Content-Disposition","attachment; filename=test.jpg");
Response.CacheControl = "public";
Response.Expires = 0;
oConn = Server.CreateObject("ADODB.Connection");
oConn.Open("DSN=ORACLE;UID=scott;PWD=tiger;");
// Query SQL to obtain recordset containing gif BLOB
oRs = oConn.Execute("SELECT JPG_FILE FROM JPG WHERE CLZM='3156'");
// Obtain local variable of /*
PicSize = oRs("JPG_FILE").ActualSize;
Pic = oRs("JPG_FILE").GetChunk(PicSize);
// ??? Obtain only 4 bytey - why ???
Response.BinaryWrite(Pic);
Response.End();
%>
Thank's
Ondrej

Answer 1

I had the same problem using VBScript.
What you have to do isread in blocks of let's say 1k in a loop and check wether the return value is exactly 1k, if not you may end your loop.
Here's my code in VBScript.
Dim varBlob
Dim varChunk
Const chuckSize = 1024
Do
varChunk = objRs.Fields("blobField").getChunk(chuckSize)
varBlob = varBlob & varChunk
Loop While (len(varChunk) = chuckSize)
the contents of varBlob is your Picture
null