Support > Database usage guide (R7) > Types of databases > Built-in database (HSQLDB)

HSQLDB is an open source relational database attached as a standard to Wagby. It is implemented in the Java language, it is characterized by its light weight and high speed. Here are points to note when using HSQLDB.

HSQLDB is shipped as a simple database for use during development.It is deprecated to use it in production applications.

  • All data is managed in memory.Because of this mechanism, the upper limit of the number of registered data varies depending on the memory capacity installed in the production machine.
  • When the Web application is terminated, the data in the memory is output as a file.Therefore, if the web application stops due to an unexpected power outage, data in the memory will be lost.Please do back up data by doing data export which is the standard function of Wagby regularly.
  • When starting the Web application, all data is read into memory.Therefore, if the amount of stored data is large, the startup time will take longer.
  • If the database file is corrupted for some reason, restore it by restoring the last exported data after initializing it once.

All types are treated as Java internal mechanisms (basic types such as int, float and standard classes such as java.lang.String).

Automatically start and stop the database at the timing of Tomcat start/stop.

Body (program)

The body (program) of hsqldb is $ (DEVHOME) \ env \ lib-common \ hsqldb.jar.After the build, it is placed in wagbyapp \ lib \ hsqldb.jar.This program also serves as a JDBC driver.

Database file

The physical file of the database is wagbyapp \ webapps \ $ (APPNAME) \ WEB - INF \ data \ $ (APPNAME) db.script.The standard is wagbydb.script.

The file is in text format.You can check the contents with a text editor.

When backing up a physical file, please save both the .script and the .properties file on the same folder.