Batch history capacity

The Archive History Provider feature allows queries against local and archived history records. The archived records come from an external data store, typically a relational database. Once the provider is configured and operational, and history data are available from an external data store, you have the opportunity to update the capacity of locally-stored histories to reduce local storage requirements.

Local histories are faster to query than archived histories, so you should consider a local history capacity setting that balances your local storage requirements with your common history query time ranges. You should also choose a local history capacity that is acceptable even on occasions when the archive data source is temporarily unavailable (for example, when the remote archive data source is down for maintenance).

Changing each capacity property individually could be a tedious process. This section documents how to use existing tools to make updating the capacity properties as easy as possible.

A locally-stored history can be:

• A local history residing on the station

• A remote history imported to the local station

• A remote history exported to the local station

Each of these requires a different set of steps, which are documented in the three task topics that follow.