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.)
CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY( 'derby.database.classpath', 'APP.ToursLogic:APP.ACCOUNTINGLOGIC')
See "derby.database.classpath" in Tuning Derby for more information about the property.