Here's a quick JDBC with HSQLDB tutorial to get you up and running with Java database connectivity and the popular HyperSQL database.

JDBC (Java Database Connectivity) is the Java API that manages connecting to a database, issuing queries and commands, and handling result sets obtained from the database.

Java Database Connectivity (JDBC) is an application program interface (API) packaged with the Java SE edition that makes it possible to standardize and simplify the process of connecting Java ...

Write, build, and run an example application that persists data to and from a relational database using Hibernate, JPA, and the repository pattern.