ABAP Keyword Documentation → ABAP − Reference → Processing External Data → ABAP Database Access → Object Services → Persistence Service
Management States in the Persistence Service
An object of a persistent class managed by the persistence service can have one of seven different management states. The state of the object affects what methods of the persistence service can be performed on it. The methods of the interface IF_OS_CA_INSTANCE provide information about the state of managed objects.
The following constants of the type group OSCON return the state of the object:
| Constant | Value | State |
|---|---|---|
| OSCON_OSTATUS_NOT_LOADED | 0 | Representative object for a persistent object, data not yet loaded from the database. |
| OSCON_OSTATUS_NEW | 1 | The object is persistent and is new. |
| OSCON_OSTATUS_LOADED | 2 | The object is persistent and has been loaded completely. |
| OSCON_OSTATUS_CHANGED | 3 | The object is persistent and has been changed. |
| OSCON_OSTATUS_DELETED | 4 | The object is persistent and has been deleted. |
| OSCON_OSTATUS_TRANSIENT | 10 | The object is transient. |
| OSCON_OSTATUS_LOADING | 12 | The object is being loaded at this moment. |
The states 0 to 4 describe persistent objects with a connection to the database. An object in state 10 is managed by the persistence service but has no connection to the database.
An object in state 12 is in transition to the state OSCON_OSTATUS_LOADED. This state can be observed only in the method INIT of the interface IF_OS_STATE, so it will not be listed in the following tables.
The table below indicates the methods of the persistence service that can be performed on objects in
different states, and how they affect the state of the managed object. The last line shows the effect of the statement COMMIT WORK.
| Method | - | 0 | 1 | 2 | 3 | 4 | 10 |
|---|---|---|---|---|---|---|---|
| CREATE_PERSISTENT | 1 | 3 | exc | exc | exc | 3 | exc |
| DELETE_PERSISTENT | - | 4 | 0 | 4 | 4 | 4 | exc |
| GET_PERSISTENT | 2 | 2 | 1 | 2 | 3 | exc | exc |
| GET_attribute | exc | 2 | 1 | 3 | 3 | exc | 10 |
| SET_attribute | exc | 3 | 1 | 3 | 3 | exc | 10 |
| REFRESH_PERSISTENT | exc | 0 | exc | 0 | exc | exc | exc |
| RELEASE | exc | - | exc | - | exc | exc | exc |
| CREATE_TRANSIENT | 10 | exc | exc | exc | exc | exc | exc |
| GET_TRANSIENT | exc | exc | exc | exc | exc | exc | 10 |
COMMIT WORK |
- | 0 | 0 | 0 | 0 | - | 10 |
All methods (except GET_attribute and SET_attribute) are methods of the class agent. For simplicity’s sake, we have summarized the class and interface methods by using typical names for them. GET_attribute and SET_attribute are methods of the persistent class.
The numbers reflect the management states. For example, the method DELETE_PERSISTENT shifts a persistent object from the state 0, 2, 3, or 4 to the state 4.
The dash (-) indicates that an object of a persistent class is available but cannot be managed. A situation
like this may occur, for example, if the system deletes a persistent object by passing a reference to
the method DELETE_PERSISTENT. The statement COMMIT WORK deletes the object from the database and it is no longer managed. However, it is persisted in the
internal session until all references to it are also deleted.
As can be seen in the table, the methods DELETE_PERSISTENT, GET_PERSISTENT, and REFRESH_PERSISTENT can work only with persistent objects in a state from 0 to 4, while GET_TRANSIENT can work only with transient objects in the state 10.
Any attempt to apply a method to a management state inappropriately raises an exception, exc.
Other versions:
7.31 | 7.40 | 7.54