Apache Derby, also known as JavaDB, is an open-source relational database management system (RDBMS) that is written in Java. It is a lightweight and embeddable database that can be used for development, testing, and production.

Here's how to get started with Apache Derby (JavaDB):

1. Download and install Apache Derby

You can download the latest version of Apache Derby from the Apache website. Choose the appropriate version for your operating system, and then follow the installation instructions.

2. Set up the environment

After installing Apache Derby, you need to set up the environment. Here's an example for setting up the environment on Windows:

• Set the DERBY_HOME environment variable to the directory where Apache Derby is installed. For example, C:\apache-derby-10.15.2.0-bin.
• Add %DERBY_HOME%\bin to the PATH environment variable.

3. Start the Derby Network Server

Before using Derby, you need to start the Derby Network Server. You can start the Network Server by running the startNetworkServer.bat (Windows) or startNetworkServer (Linux) script in the bin directory of your Derby installation.

4. Create a database

After starting the Derby Network Server, you can create a new database using the ij tool. The ij tool is a command-line tool that allows you to interact with Derby using SQL commands.

To create a new database, open a command prompt or terminal and run the following command:

ij> connect 'jdbc:derby://localhost:1527/mydb;create=true';

This command connects to the Derby Network Server and creates a new database called mydb.

5. Use the database

After creating the database, you can use it by running SQL commands. Here's an example:

ij> create table my_table (id int primary key, name varchar(50));
ij> insert into my_table values (1, 'John');
ij> select * from my_table;

This example creates a new table called my_table with two columns (id and name). It then inserts a new row into the table and retrieves all the rows in the table.

These are the basic steps to get started with Apache Derby (JavaDB). There are many more features and options that you can explore as you become more familiar with the database.