HSQLDB

HSQLDB (Hyper Structured Query Language Database ) is a free, fully programmed in Java and SQL relational database ( RDBMS) and is available under a free license after the pattern of the BSD license. The project describes itself as " Lightweight 100 % Java SQL Database Engine" and is based on Thomas Mueller's no longer discontinued Hypersonic SQL Project.

With to the HSQL packet along with the server is a SQL client ( Database Manager), which works in both server as well as in stand-alone mode. HSQL can be integrated as an embedded database system into other applications.

Properties

In the HSQL speed is roughly equivalent to MySQL. The data stored on the disk table types can be operated in read mode, which is, for example, for projects on CD-/DVD-Datenträgern beneficial. HSQL is integrated in OpenOffice.org 2.0, to provide a MS-Access -like application.

. HSQL supports a large part of the SQL standards 92, 99 and 2003 HSQL is available in several versions:

  • Standard version, as it is integrated, for example, in the Application Server wildfly
  • Special versions for PDA and handheld

Unlike other database systems

HSQL it differs from other database systems in many ways:

  • Size: hsqldb.jar is only ~ 1 MB in size.
  • Integration: The package comes with both an HSQL server, the SQL requests from the network ( via JDBC) receive, as well as the ability to run the database server without fully and thus to integrate into a program. The communication is then only through API calls and not over the network vonstatten.
  • Flexibility: as table types, the following types are available: Memory only: All data are stored only in memory and not stored on the disk. Changes will be lost when you quit the server (or the application in standalone mode).
  • Log file tables: all SQL commands that change the table data (CREATE, ALTER, INSERT, UPDATE) are stored in a large SQL log file. The log file is processed again each time and then stored in memory.
  • Cached tables stored on disk tables that do not have to be completely read into memory at startup. The size limit of a table and a field currently stands at 8 GB. Working on such tables will be very fast.

With HSQLDB related products

The original developer Thomas Müller is currently working on the open source database H2 Database, which has similar aims as HSQLDB.

BSD licenses CD-ROM Microsoft Access Java Database Connectivity Table (database) Cache (computing) H2 (DBMS)
401233
de