Java JDBC Update SQL Query Example

In this example, we will discuss how to update a record in a MySQL database table via a JDBC statement.

 Learn a complete JDBC tutorial at https://www.javaguides.net/p/jdbc-tutorial.html.

Fundamental Steps in JDBC

The fundamental steps involved in the process of connecting to a database and executing a query consist of the following:

  1. Import JDBC Packages
  2. Establishing a connection.
  3. Create a statement.
  4. Execute the query.
  5. Using try-with-resources statements to automatically close JDBC resources.

Key points

  1. From JDBC 4.0, we don't need to include 'Class.forName()' in our code to load JDBC driver. JDBC 4.0 drivers that are found in your classpath are automatically loaded.
  2. We have used try-with-resources statements to automatically close JDBC resources.

JDBC Statement Update Record Example

Below example update a single record in a database table.
Check out below articles before updating the record:
>> JDBC Statement Create a Table Example
>> JDBC Statement - Insert Multiple Records Example

In the below JDBC example, we are using the UPDATE SQL statement to update record to the database table: 

package com.javaguides.jdbc.statement.examples;

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

/**
 * Update Statement JDBC Example
 * @author Ramesh Fadatare
 *
 */
public class UpdateStatementExample {

    private static final String UPDATE_USERS_SQL = "update users set name = \"Ram\" where id = 1;";

    public static void main(String[] argv) throws SQLException {
        UpdateStatementExample updateStatementExample = new UpdateStatementExample();
        updateStatementExample.updateRecord();
    }

    public void updateRecord() throws SQLException {
        System.out.println(UPDATE_USERS_SQL);
        // Step 1: Establishing a Connection
        try (Connection connection = DriverManager
            .getConnection("jdbc:mysql://localhost:3306/mysql_database?useSSL=false", "root", "root");

            // Step 2:Create a statement using connection object
            Statement statement = connection.createStatement();) {

            // Step 3: Execute the query or update query
            int result = statement.executeUpdate(UPDATE_USERS_SQL);
            System.out.println("Number of records affected :: " + result);
        } catch (SQLException e) {

            // print SQL exception information
            printSQLException(e);
        }

        // Step 4: try-with-resource statement will auto close the connection.
    }

    public static void printSQLException(SQLException ex) {
        for (Throwable e: ex) {
            if (e instanceof SQLException) {
                e.printStackTrace(System.err);
                System.err.println("SQLState: " + ((SQLException) e).getSQLState());
                System.err.println("Error Code: " + ((SQLException) e).getErrorCode());
                System.err.println("Message: " + e.getMessage());
                Throwable t = ex.getCause();
                while (t != null) {
                    System.out.println("Cause: " + t);
                    t = t.getCause();
                }
            }
        }
    }
}
Output:
update users set name = "Ram" where id = 1;
Number of records affected :: 1

References



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