ResultSet Cursor and Scrollability

This section describes what is ResultSet cursor and ResultSet scrollability.

Each ResultSet object maintains a cursor (pointer) to identify the current data row. The cursor of a newly created ResultSet object is positioned before the first row. How to move the cursor is depending on the scrollability of the ResultSet.

1. Non-scrollable ResultSet - The ResultSet object type is ResultSet.TYPE_FORWARD_ONLY, the default type. Non-scrollable ResultSet supports only cursor move method:

2. Scrollable ResultSet - The ResultSet object type is ResultSet.TYPE_SCROLL_INSENSITIVE, or ResultSet.TYPE_SCROLL_SENSITIVE. Scrollable ResultSet supports a number of cursor move methods:

Here is a sample program that loops through the ResultSet rows forward only with next() method:

 * Copyright (c) All Rights Reserved.
import java.sql.*;
public class DerbyLoopResultSet {
  public static void main(String [] args) {
    Connection con = null;
    try {
      con = DriverManager.getConnection("jdbc:derby://localhost/TestDB");
      Statement sta = con.createStatement();

// Catch the ResultSet object
      ResultSet res = sta.executeQuery("SELECT * FROM Profile");

// Check ResultSet's scrollability
      if (res.getType() == ResultSet.TYPE_FORWARD_ONLY) {
        System.out.println("ResultSet non-scrollable.");
      } else {
        System.out.println("ResultSet scrollable.");

// Move cursor forward only with next()
      System.out.println("List of Profiles:");
      while ( {
        String firstName = res.getString("FirstName");
        String lastName = res.getString("LastName");
        System.out.println("   "+firstName+" "+lastName);

// Close ResultSet

    } catch (Exception e) {
      System.err.println("Exception: "+e.getMessage());

The output is listed below:

ResultSet non-scrollable.
List of Profiles:
   Janet Gates
   256d aa3f5
   8ef 466ca
   10cc ab361
   11bd 99552
   8c4 68909
   17e1 99a5d
   1ea2 480c7
   Keith Harris

Table of Contents

 About This Book

 JDBC (Java Database Connectivity) Introduction

 JDK (Java SE) Installation

 Installing and Running Derby (Java DB)

 Derby (Java DB) JDBC Driver

 Derby (Java DB) JDBC DataSource Objects

 Derby (Java DB) - DML Statements

Derby (Java DB) - ResultSet Objects of Queries

 What Is ResultSet?

ResultSet Cursor and Scrollability

 ResultSet Cursor Initial Position: Before First Row

 Retrieving Column Values with getXXX() Methods

 ResultSet Default Type: Forward-only

 Scrollable ResultSet and Moving Cursor Backward

 ResultSet Objects with Update Capability

 insertRow() - Inserting New Rows through ResultSet Objects

 updateXXX() - Updating Column Values for Row Update or Insert

 deleteRow() - Deleting Rows through ResultSet Objects

 Derby (Java DB) - PreparedStatement

 Summary of JDBC Drivers and Database Servers

 Using Connection Pool with JDBC

 Archived Tutorials


 Full Version in PDF/EPUB