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These tables hold information about the state of the object and all object data. After creation of a persistent state object, only the object's state machine diagram defines its life cycle. This means, only events defined in the state machine diagram can change object states and object data (for details see State Machine Diagrams).

Events in this context are:

• completion event: triggered by an automatic state transition
• signal event: triggered by a signal reception
• time event: triggered by a time trigger

For example, signals sent to the object transport data that can be added to the object. However, it is not possible to retrieve the object from the database, manipulate it, and write it back afterwards – though it is possible to retrieve a copy of a persisted object from the database. This means, after having created a persistent state object, the object lives on the database until it reaches its final state. Again, the object's state machine diagram defines which events may trigger the transition into its final state. If the object reached its final state, it will be deleted.

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It is not necessary to adapt database schemas when changing the structure of the persisted data because the database tables are generic. This makes the database model flexible and robust.

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