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Johnny Pachecp
Asked: 2020-09-22 08:31:45 +0800 CST 2020-09-22 08:31:45 +0800 CST

Local Database in Java

  • 772

I want to develop a website that works with MySQL, but at the same time I want that platform to be able to be used from desktop software. I'm doing it with java, and I'm new to it, I want to know how I could use a completely local database with java, which is MySQL, in such a way that I can use it as a mirror database, of which the website uses.

java

3 Answers

  1. What you need is a distributed database, the changes you make in the master DB will be replicated in the slave DB, and the modifications can be made in several ways, this is a DB problem.

    I recommend that you read the following article , where they explain this topic very well and help you to make an example.

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  2. Best Answer

    The truth is that at the time of development, the database of a web app and a desktop app do not differ.

    • IMPORTANT: before connecting, you must create one BBDDwith MySQLits corresponding user and administrator password.

      If you don't want to complicate your life, use MySQL WorkBench or any other graphical interface

    Register the driver in your system ( NOTE: the jar has to be in the classpath!!! ):

    try {
    Class.forName("com.mysql.jdbc.Driver");
    System.out.println("Driver registrado con existo!");
} catch (ClassNotFoundException e) {
    throw new IllegalStateException("No se ha encontrado el driver en el classpath!", e);
}

    Configure connection to DB:

    With MysqlDataSource(preferred form)

    MysqlDataSource dataSource = new MysqlDataSource();

// usuario y pass
dataSource.setUser("usuario");
dataSource.setPassword("password");

// servidor y puerto (he puesto el 3306 que es el std, pero cambialo sino!)
dataSource.setServerName("localhost");
dataSource.setPort(3306);

// base de datos creada
dataSource.setDatabaseName("nombreBBDD");

// crear conexion a partir de los datos 
Connection conn = dataSource.getConnection();

    Another older way is usingDriverManager :

    String URL = "jdbc:mysql:3306//localhost/nombreBBDD";
String USER = "username";
String PASS = "password"
Connection conn = DriverManager.getConnection(URL, USER, PASS);

    Once done, you can make a query like this:

    Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("SELECT * FROM TU_TABLA");

// haz cosas con el resultado!

rs.close();
stmt.close();
conn.close();

    SOURCES 1 , 2

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  3. If the users are few and the local db can work in read mode, it is worth configuring a local replica of the master db used by the web server.

    Edited 09-26-2016:

    What you say can be done, but I don't know of any out-of-the-box solutions. I did it myself with a "dirty" table with two columns. Join the table that contained the dirty and its id. This way I could find locally modified ones easily and quickly, and more importantly, if there are local changes to sync.

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