请问这句话怎么理解?
在                         pstmt = conn.prepareStatement(sql); pstmt.setString(1, user.getName());
pstmt.setString(2, user.getPassword());
pstmt.setInt(3, user.getValid());
pstmt.setString(4, user.getEmail());
pstmt.setString(5, user.getPhone());
pstmt.setTimestamp(6, new Timestamp(new Date().getTime()));
pstmt.executeUpdate();
中,假如不写   pstmt = conn.prepareStatement(sql);这一句行吗?