deleteRow() - Deleting Rows through ResultSet Objects

This section describes how to delete rows from target tables through ResultSet objects.

A ResultSet object with update capability can also be used to delete rows from database tables. All you need to do are:

I wrote the following sample program to test this feature:

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

// Create a Statement for scrollable ResultSet
      Statement sta = con.createStatement(
        ResultSet.TYPE_FORWARD_ONLY,
        ResultSet.CONCUR_UPDATABLE);

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

// Check ResultSet's updatability
      if (res.getConcurrency() == ResultSet.CONCUR_READ_ONLY) {
        System.out.println("ResultSet non-updatable.");
      } else {
        System.out.println("ResultSet updatable.");
      }

// Looping through the rows in the ResultSet object
      while (res.next()) {
        int id = res.getInt("ID");
        if (id == 4 || id == 6) {
          res.deleteRow();
        }
      }
      System.out.println("Rows deleted ok.");

// Close ResultSet and Statement
      res.close();
      sta.close();

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

Two rows were deleted from the Profile table:

ResultSet updatable.
Rows deleted ok.

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

 References

 Full Version in PDF/EPUB