How to Update Database Records in Java?

The following program demonstrates How to Update Database Records in Java.

To update records in a database using Java, you can use the JDBC (Java Database Connectivity) API. Here’s an example of how to update records in a MySQL database.

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;

public class UpdateRecordsDemo {
    public static void main(String[] args) {
        // Database connection parameters
        String url = "jdbc:mysql://localhost:3306/mydatabase";
        String username = "your_username";
        String password = "your_password";

        // Data for updating records
        int idToUpdate = 1; // Specify the ID of the record to update
        String newName = "Updated Name";
        int newAge = 35;

        try {
            // Establish a database connection
            Connection connection = DriverManager.getConnection(url, username, password);

            // Create an SQL UPDATE statement
            String updateSql = "UPDATE mytable SET name = ?, age = ? WHERE id = ?";

            // Create a prepared statement
            PreparedStatement preparedStatement = connection.prepareStatement(updateSql);

            // Set parameter values
            preparedStatement.setString(1, newName);
            preparedStatement.setInt(2, newAge);
            preparedStatement.setInt(3, idToUpdate);

            // Execute the UPDATE statement
            int rowsUpdated = preparedStatement.executeUpdate();

            if (rowsUpdated > 0) {
                System.out.println("Records updated successfully.");
            } else {
                System.out.println("No records updated.");
            }

            // Close resources
            preparedStatement.close();
            connection.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

In this program:

Import the necessary JDBC classes.
Specify the database connection parameters (URL, username, and password) to connect to your MySQL database.
Define the data for updating records: idToUpdate specifies the ID of the record to update, and newName and newAge are the new values you want to set for the record.
Establish a database connection using DriverManager.getConnection.
Create an SQL UPDATE statement with placeholders (?) for the values to be updated.
Also, create a PreparedStatement to execute the SQL statement.
Set parameter values using setString and setInt.
Execute the UPDATE statement using executeUpdate.
Check the number of rows updated to determine if the operation was successful.
Close resources (prepared statement and connection) in a finally block or using try-with-resources.

Make sure to replace the following placeholders with your own database information:

url: The JDBC URL of your MySQL database.
username: Your database username.
password: Your database password.

Ensure that your MySQL database server is running and that the specified database and table exist with the appropriate schema. Also, confirm that the ID specified in idToUpdate exists in the table.

Further Reading