Using the Embedded SQL Database Engine
HSYCO embeds HSQLDB (HyperSQL Database), a powerful SQL database engine you can use in your applications via the standard JDBC API.
HSQLDB (HyperSQL DataBase) is a leading SQL relational database engine written in Java. It has a JDBC driver and supports nearly full ANSI-92 SQL plus many SQL:2008 enhancements. All HSQLDB documentation is available at: http://hsqldb.org.
The JDBC API is the industry standard for database-independent connectivity between the Java programming language and a wide range of databases. The JDBC API provides a call-level API for SQL-based database access. The JDBC documentation is available at: http://java.sun.com/products/jdbc/overview.html.
HSQLDB offers a small, fast, multithreaded and transactional database engine which offers in-memory and disk-based tables and supports embedded and server modes.
HSQLDB is directly integrated in the core HSYCO package, so there is no need to add any additional jar file to the HSYCO classpath.
The database that HSYCO uses is called “hsyco” and its files are saved in the data/ directory under the base directory, where hsyco.ini and all other configuration files are also located.
We consider the data/ directory a reserved HSYCO path and discourage the use of it for storing user’s databases or in general for any customized purpose.
We suggest using userdata/ as the general base path for all customized file storage needs, including the location of your own HSQLDB databases.
HSYCO uses HSQLDB to store persistent variables.
It is very likely that we will use it for other purposes in the future, so it is important that you follow a few simple guidelines to avoid potential conflicts in future releases.
Moreover, the resources load of the SQL engine has a direct impact on the performance and stability of HSYCO SERVER.