Archive databases preserve batch data and ensure the main database has sufficient resources to continue logging batch and chronicle events. Batch and chronicle events are initially incorporated into the main Batch Historian database (DVHisDB). Once the batch and chronicle events are archived and deleted from the main database, a standard backup of the main DVHisDB database no longer includes the archived data. To prevent potential loss of data, it is recommended that you backup archive databases before deleting the data from the main database. Once the backup of the archive database is complete, you can safely remove the archived batches and chronicle events from the main database.
Use the DeltaV Batch Historian Administrator Interface to manage batch and chronicle event data. Resources for the Batch Historian workstation include both the space available to the Main database and space available on the hard drive.
Space available to the main Batch Historian database enables the Historian to incorporate new batch and chronicle events. Archiving and deleting batch and chronicle events from the main database ensures this space is available. It is recommended that you make backups of the archive databases before deleting the events from the main database.
Space available on a workstation's hard disk allows the SQL Server to complete tasks without running into resource issues. Once an archive database is created and populated, its files can be moved to another storage location to free up the necessary disk space for the SQL Server. At a later time, you can move the archive database files back to the workstation for analysis. The SQL Server requires the standard 500 MB page file as a minimum requirement on a DeltaV workstation.
You need to understand the meaning of the terms attached and detached when managing archive database files. When a database is attached, the data in the archive can be queried and viewed with the DeltaV Batch History View application or another database client. When a database is detached, the files can be copied to another storage location and deleted from the hard drive to free up disk space but a detached database cannot be accessed by Batch History View or another database client.