NexusDB

NexusDB real time backup and restore component.  Default values are shown in the object inspector snapshot.

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Properties and Events view

Purpose

The TnxBackupController is a real-time backup component which enables you to make a backup of a database while it is in use.  Simply assign source and target database components, which may or may not reside on the same server.  Events are available to filter which tables are backed up.  To save space and time, the backed up version of the tables as default do not contain indices.  If required, the TnxBackupController can be used to restore tables from the backup.  The indices will be recreated during the restore procedure.

If the two databases (original and backup) are on separate servers, the data is sent from the source server to the client and then to the target server using batch read and writes.  If both databases reside on a single server, a direct transfer takes place with no data being sent across the network to the client.

The entire process occurs within a snapshot transaction.  Therefore, the database is guaranteed to be in a consistent state.  NOTE: Restoring tables requires exclusive access to the destination alias; this is to ensure data consistency.

While running the backup process, the server needs enough RAM and temporary storage to cache all updates from other sources.  The restore process requires exclusive access to the target (restored) directory.

Key Properties

Key Events

These events allow you to do custom processing during the backup process.

Please also see Common Properties and Events for more details.