Reading and Writing LOBs En Bloc

Use

Reading and writing LOBs en bloc implies that either you retrieve the value of the BLOB and CLOB columns into a byte array or a string, or you insert data from a byte array or a string.

Activities

Reading LOBs en Bloc

The JDBC API provides the methods getBytes() and getString() methods of java.sql.ResultSet . They enable you to read BLOB or CLOB columns into a byte array or a string respectively.

Reading LOBs en Bloc using JDBC

               String query = "select REFMANUAL, PICTURE from BC_CR_VEHICLE " +
        "where NAME = ?";
PreparedStatement ps = conn.prepareStatement(query);
try {
  ps.setString(1, "Golf");
  ResultSet rs = ps.executeQuery();
  try {
        while (rs.next()) {
                String refManual = rs.getString("REFMANUAL");
                byte[] image = rs.getBytes("PICTURE");
  ...
        }
  finally {
        rs.close();
  }
finally {
  ps.close();
}

Writing LOBs en Bloc

To insert data from a byte array or a string with JDBC , you should use setBytes() or setString() methods of java.sql.PreparedStatement .

Writing LOBs en Bloc using JDBC

               String manual = "...";
byte[] picture = ...;

String insertStmt = "insert into VEHICLE " +
        "(NAME, REFMANUAL, PICTURE) VALUES (?, ?, ?)";
PreparedStatement ps = conn.prepareStatement(insertStmt);
try {
        ps.setString(1, "Golf");
        ps.setString(2, manual);
        ps.setBytes(3, picture);
        ps.executeUpdate()
}finally{
ps.close();
}