Message-ID: <39705864.8CABD64F@radix.com.br>
Date: Sat, 15 Jul 2000 09:26:13 -0300
From: Nelson Ferreira Jr <nelson@radix.com.br>
MIME-Version: 1.0
To: pgsql-interfaces@postgresql.org
Subject: JDBC - error reading BLOBs
Content-Type: text/plain; charset=us-ascii
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 Hi,

  I got the following error when reading BLOBs from a database.
Everything
works fine when there is a few concurrent requests, but when putting the

servlet in a heavy-load situation, I got the following errors:

ERROR:  lo_tell: invalid large object descriptor (0)
ERROR:  lo_close: invalid large obj descriptor (1)
ERROR:  lo_read: invalid large obj descriptor (1)
ERROR:  lo_lseek: invalid large obj descriptor (1)

  It only happens with 10 or more concurrent requests, and about 5% of
the
requests fails. Here is the code:


--------------------------------------------------------------------
   con.setAutoCommit(false)
   pstmt =con.prepareStatement(query_gif);
   ResultSet rs_gif = pstmt.executeQuery();

   if (rs_gif.next()) {
       BufferedInputStream gifDados = new
       BufferedInputStream(rs_gif.getBinaryStream("GIF"));
       byte[] buf =new byte[4*1024]; //4Kb buffer
       int tam;
       while ((tam =gifDados.read(buf,0,buf.length)) != -1){
           out.write(buf,0,tam); // Its the PrintWriter of my Servlet
       }
      }
      con.setAutoCommit(true);

--------------------------------------------------------------------


    I am runnig postgreSQL 7.0.2 on a RedHat 6.2 linux


                                                  Thanks