# Enable database class loading with a property

Once you have added one or more jar files to a database, you must set the database jar "classpath" by including the jar file or files in the derby.database.classpath property to enable Derby to load classes from the jar files.

This property, which behaves like a class path, specifies the jar files to be searched for classes and resources and the order in which they are searched. If Derby does not find a needed class stored in the database, it can retrieve the class from the user's classpath. (Derby first looks in the user's classpath before looking in the database.)

- Separate jar files with a colon (:).
- Use two-part names for the jar files (schema name and jar name). Set the property as a database-level property for the database. The first time you set the property, you must reboot to load the classes.

Example:

    CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY(
        'derby.database.classpath',
        'APP.ToursLogic:APP.ACCOUNTINGLOGIC')

See "derby.database.classpath" in Tuning Java DB for more information about the property.

Note: Derby's class loader looks first in the user's classpath for any needed classes, and then in the database. To ensure class loading with the database class loader, remove classes from the classpath.
Parent topic: Class loading overview
Previous topic: Add the jar file or files to the database
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Related concepts
Dynamic changes to jar files or to the database jar classpath
Signed jar files