This is an example of how to delete all table rows in Java. In order to delete all rows of a table we can use TRUNCATE, because it does not generate rollback information and does not fire any delete triggers, so it is faster than DELETE. Deleting all table rows implies that you should:
- Load the JDBC driver, using the
forName(String className)API method of the Class. In this example we use the MySQL JDBC driver. - Create a Connection to the database. Invoke the
getConnection(String url, String user, String password)API method of the DriverManager to create the connection. - Create a Statement, using the
createStatement()API method of the Connection. - Invoke the
executeUpdate(String sql)API method of Statement in order to execute the TRUNCATE query.
Let’s take a look at the code snippet that follows:
package com.javacodegeeks.snippets.core;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
public class TruncateExample {
public static void main(String[] args) {
Connection connection = null;
try {
// Load the MySQL JDBC driver
String driverName = "com.mysql.jdbc.Driver";
Class.forName(driverName);
// Create a connection to the database
String serverName = "localhost";
String schema = "test";
String url = "jdbc:mysql://" + serverName + "/" + schema;
String username = "username";
String password = "password";
connection = DriverManager.getConnection(url, username, password);
System.out.println("Successfully Connected to the database!");
} catch (ClassNotFoundException e) {
System.out.println("Could not find the database driver " + e.getMessage());
} catch (SQLException e) {
System.out.println("Could not connect to the database " + e.getMessage());
}
try {
Statement statement = connection.createStatement();
/* TRUNCATE is faster than DELETE since
* it does not generate rollback information and does not
* fire any delete triggers
*/
statement.executeUpdate("TRUNCATE test_table");
System.out.println("Successfully truncated test_table");
} catch (SQLException e) {
System.out.println("Could not truncate test_table " + e.getMessage());
}
}
}
Example Output:
Successfully Connected to the database!
Successfully truncated test_table
This was an example of how to delete all table rows in Java.
