JDBC Tutorials - Herong's Tutorial Examples - v3.13, by Herong Yang
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
JDBC (Java Database Connectivity) Introduction
Installing and Running Derby (Java DB)
Derby (Java DB) JDBC DataSource Objects
Derby (Java DB) - DML Statements
►Derby (Java DB) - ResultSet Objects of Queries
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