class RDbNotifier |
Provides notification of database changes to clients.
This is useful for shared databases.
Public Member Functions | |
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IMPORT_C void | Cancel() |
IMPORT_C void | Close() |
IMPORT_C void | NotifyChange(TRequestStatus &) |
IMPORT_C void | NotifyUnlock(TRequestStatus &) |
IMPORT_C TInt | Open(RDbDatabase &) |
Public Member Enumerations | |
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enum | TEvent { EClose, EUnlock, ECommit, ERollback, ERecover } |
Private Attributes | |
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RDbHandle< CDbNotifier > | iNotifier |
IMPORT_C void | NotifyChange | ( | TRequestStatus & | aStatus | ) |
TRequestStatus & aStatus |
IMPORT_C void | NotifyUnlock | ( | TRequestStatus & | aStatus | ) |
TRequestStatus & aStatus |
Defines the events which may be reported by a DBMS change notifier through this RDbNotifier object.
Each enumerator corresponds to a distinct event type.
The changes are reported through a TRequestStatus object when an outstanding notification request completes.
Notes
If further database events occur while a client is handling the completion of a previous event, the notifier remembers the most significant event. The order of importance is:
ERecover > ERollback > ECommit
where the symbol > means "is more important than"
EClose |
The database has been closed. |
EUnlock |
All read locks have been removed. |
ECommit |
A transaction has been committed. |
ERollback |
A transaction has been rolled back |
ERecover |
The database has been recovered |