Solved

Stream from SQL RS to a file

Posted on 2004-04-29
7
319 Views
Last Modified: 2010-03-31
Hi,

I am currently making a program, which is getting data from SQL Server DB (using jTDS) into a resultset. This resultset is then looped for every row and then written to a random access file. Now my question is, how I could do this so the program could just dump all the data to a file without any looping? I was thinking of using a direct stream from input to output, this is possible, right?

See below the code (it's working, but it's extremely slow in bigger amount of SPs and not all characters are written to the file as they should be)...

 
<--- begin of code --->

import net.sourceforge.jtds.jdbc.Driver;
import java.io.*;
import java.sql.*;
public class CreateFiles {
      public static void main(String[] args) throws Exception {
            try
            {
                  String url="jdbc:jtds:sqlserver://mssql-server:1433";
                  String usr = "sql";
                  String passwd = "sql";
                  Class.forName("net.sourceforge.jtds.jdbc.Driver");
                  Connection conn=DriverManager.getConnection(url, usr, passwd);
                  conn.setCatalog("TestDB");
                  ResultSet rs = null;
                  CallableStatement proc = null;
                  String fileName = "";
                  String theData = "";
                  fileName = "FirstFile";

                  proc = conn.prepareCall("{ call sp_Java_GetTest  }");
                  rs = proc.executeQuery();
                  while(rs.next())
                  {
                        theData = theData + rs.getString(1) + rs.getString(2)
                        + rs.getString(3) + rs.getString(4);
                  }
                  rs.close();
                  rs = null;

                  proc = conn.prepareCall("{ call sp_Java_GetTest2  }");
                  rs = proc.executeQuery();
                  while(rs.next())
                  {
                        theData = theData + rs.getString(1) + rs.getString(2)
                        + rs.getString(3) + rs.getString(4) + rs.getString(5);
                  }
                  rs.close();
                  rs = null;


                  writeFile(fileName, theData);
                  theData = "";



    public static void writeFile(String f, String s) throws IOException
    {
            try
            {
                  RandomAccessFile rf = new RandomAccessFile(f, "rw");
                  rf.writeBytes(s);
                  rf.close();
            }
            catch (IOException e)
            {
                  System.err.println (e);
            }
      }

}

<--- end of code --->

So as you can see, the idea is to write to one file data from different SPs.

Hope you can help me out with this one!
0
Comment
Question by:planeman
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
7 Comments
 
LVL 92

Assisted Solution

by:objects
objects earned 125 total points
ID: 10947885
You could loop thru the result set and write to say a FileOutputStream .
You can't avoid looping thru the result set thought, that is how results are read.
0
 
LVL 30

Accepted Solution

by:
Mayank S earned 125 total points
ID: 10948489
If the RS is very huge, you could read it initally into a CachedRowSet and then disconnect from the database. Scrolling through the CachedRowSet would be faster, but well - you have to scroll ;-)
0
 
LVL 30

Expert Comment

by:Mayank S
ID: 11683278
Please proceed with that recommendation.
0
 
LVL 30

Expert Comment

by:Mayank S
ID: 11687442
Why a C :-( ?
0
 
LVL 30

Expert Comment

by:Mayank S
ID: 11703371
Thanks, modulo.
0

Featured Post

Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
numbers ascending pyramid 101 262
tomcat startup error 5 160
jsp CRUD operations with and without prepared statement also hibernatge 1 46
import as existing maven project 3 75
Are you developing a Java application and want to create Excel Spreadsheets? You have come to the right place, this article will describe how you can create Excel Spreadsheets from a Java Application. For the purposes of this article, I will be u…
In this post we will learn different types of Android Layout and some basics of an Android App.
Viewers learn about the scanner class in this video and are introduced to receiving user input for their programs. Additionally, objects, conditional statements, and loops are used to help reinforce the concepts. Introduce Scanner class: Importing…
This video teaches viewers about errors in exception handling.
Suggested Courses

738 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question