A Java MySQL INSERT example (using PreparedStatement)

Java MySQL INSERT example: Can you share a Java MySQL INSERT example, specifically using a Java PreparedStatement object?

Sure. As the question implies, you can use the Java Statement class to issue a MySQL INSERT statement, but the Java PreparedStatement class provides a much better way to insert data into a MySQL database table. (That being said, you can learn more about the Java Statement class in this Using SQL INSERT with Java Statement tutorial if you’re interested.)

An example MySQL database table

The first thing we’ll need is an example MySQL database table. To keep it simple, but to also show several different MySQL data types, I created the following MySQL example database table:

create table users (
  id int unsigned auto_increment not null,
  first_name varchar(32) not null,
  last_name varchar(32) not null,
  date_created timestamp default now(),
  is_admin boolean,
  num_points int,
  primary key (id)
);

A few of these MySQL fields are a little contrived, but I wanted to show several different data types in one table, so this is what I came up with. In particular, the field num_points is a little weird. I made it up so I could show a MySQL int data type in this table, and I was thinking of those websites where points are awarded for giving correct answers.

Other than that, this MySQL database table is relatively normal, though it is greatly simplified.

Example source code

Given that MySQL database table design, let's assume that we just want to insert one record into this MySQL table. To do so, we just need to follow these steps:

1. Create a Java Connection to our example MySQL database.
2. Create a SQL INSERT statement, using the Java PreparedStatement syntax.
3. Set the fields on our Java PreparedStatement object.
4. Execute a Java PreparedStatement.
5. Close our Java MYSQL database connection.
6. Catch any SQL exceptions that may come up during the process.

I've tried to document the following Java MySQL INSERT example so you can see these steps. Note that in this example my MySQL database username is "root", my password is blank, and the MySQL database is running on the same computer where this program is run, so the database host name is "localhost".

import java.sql.*;
import java.util.Calendar;

/**
 * A Java MySQL PreparedStatement INSERT example.
 * Demonstrates the use of a SQL INSERT statement against a
 * MySQL database, called from a Java program, using a
 * Java PreparedStatement.
 * 
 * Created by Alvin Alexander, http://alvinalexander.com
 */
public class JavaMysqlPreparedStatementInsertExample
{

  public static void main(String[] args)
  {
    try
    {
      // create a mysql database connection
      String myDriver = "org.gjt.mm.mysql.Driver";
      String myUrl = "jdbc:mysql://localhost/test";
      Class.forName(myDriver);
      Connection conn = DriverManager.getConnection(myUrl, "root", "");
    
      // create a sql date object so we can use it in our INSERT statement
      Calendar calendar = Calendar.getInstance();
      java.sql.Date startDate = new java.sql.Date(calendar.getTime().getTime());

      // the mysql insert statement
      String query = " insert into users (first_name, last_name, date_created, is_admin, num_points)"
        + " values (?, ?, ?, ?, ?)";

      // create the mysql insert preparedstatement
      PreparedStatement preparedStmt = conn.prepareStatement(query);
      preparedStmt.setString (1, "Barney");
      preparedStmt.setString (2, "Rubble");
      preparedStmt.setDate   (3, startDate);
      preparedStmt.setBoolean(4, false);
      preparedStmt.setInt    (5, 5000);

      // execute the preparedstatement
      preparedStmt.execute();
      
      conn.close();
    }
    catch (Exception e)
    {
      System.err.println("Got an exception!");
      System.err.println(e.getMessage());
    }
  }
}

Results

After running this Java MySQL INSERT example program, when you query your MySQL database table like this:

select * from users;

you should see some output like this:

+----+------------+-----------+---------------------+----------+------------+
| id | first_name | last_name | date_created        | is_admin | num_points |
+----+------------+-----------+---------------------+----------+------------+
|  1 | Barney     | Rubble    | 2010-06-23 14:02:00 |        0 |       5000 | 
+----+------------+-----------+---------------------+----------+------------+
1 row in set (0.00 sec)

This shows that the Java MySQL INSERT PreparedStatement example worked properly.

Summary: A Java MySQL INSERT example using PreparedStatement

I hope this Java MySQL INSERT example (using a PreparedStatement) makes sense as is. In "real world" Java database programs I almost always use Spring to access a database, but when you're first getting started, I think it's important to see examples like this so you can understand how things work under the covers. This example specifically shows:

1. How to connect to a MySQL database.
2. How to create a Java Date object.
3. How to create a Java PreparedStatement with a SQL INSERT query.
4. How to set the fields on a variety of different data types.
5. How to execute the Java PreparedStatement.
6. One way to confirm that our data was successfully inserted into our MySQL database.

As usual, if you have any questions or comments about this Java MySQL INSERT example, just use the Comment form below.