HistorianThe Data Store Options Section
This topic describes the fields in each subsection in the Data Store Options section.
The Archive Creation or the SCADA BufferSubsection
The Archive Creation subsection appears only if the data store type is historical. The SCADA Buffer subsection appears only if the data store type is SCADA buffer.
| Field | Description |
|---|---|
| Automatically Create Archives | Identifies whether the server must automatically create an archive file whenever the current archive file is full. The archive files are created in the default path directory. Note: If you plan to create multiple archives at the same time, select the Disabled option.
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| Overwrite Old Archives | When enabled, the system replaces the oldest archived data with new data when the default size has been reached. Since this action deletes historical data, exercise caution in using this feature. We recommend that you back up the archive so that you can restore it later. Note: To create multiple archives at the same time, select the Disabled option. If both the Automatically Create Archives and Overwrite Old Archives are enabled, set the ihArchiveFreeSpaceHardLimit parameter to TRUE using the Historian APIs. |
| Default Size (MB) | The default size of a newly created archive or the duration of a newly created archive in days or hours. Select one of the following options:
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| SCADA Buffer Duration (Days) | Indicates the maximum number of days you want to store the trend data. The maximum number of days is equal to the value of the Rotational Buffer Duration shown in the GE Licence Client. |
| Archive Duration (Days/Hours) | Indicates the days or hours for which the duration of the archive is set. |
The Maintenance Subsection
| Field | Description |
|---|---|
| Default Archive Path | The folder path to store newly created archives. Note: We recommend not to use a period in the default archive path field. If you do so, you will not be able to specify a default archive name. |
| Default Backup Path | The location to which the backup file will be saved. |
| Base Archive Name | A prefix that you want to add to all the archive files. |
| Free Space Required (MB) | Indicates the remaining disk space required after a new archive is created. If the available space is less than the requirement, a new archive is not created. The default value is 5000 MB. This field is not applicable to alarms and events archives. The alarms and events archiver will continue writing to the alarms and events archive until the drive is full. If this occurs, the alarms and events archiver will buffer incoming alarms and events data until the drive has free space. An error message is logged in the Historian message log. |
| Store OPC Quality | Indicates whether to store the OPC data quality. Note: To create multiple archives at the same time, select the Disabled option. |
| Use Caching | Indicates whether caching must be enabled. When reading data from the archiver, some data is saved in the system memory and retrieved using caching. This results in faster retrieval as the data is already stored in the buffer. Note: This option is not available for SCADA Buffer data stores. |
The Security Subsection
| Field | Description |
|---|---|
| Data is Read-only After (Hours) | The number of hours for data to be stored in a read/write archive. After the time lapses, that portion of the archive file is automatically made read-only. Incoming data values with timestamps prior to this time are rejected. A single archive file, therefore, may have a portion made read-only, another portion that is read/write containing recently written data, and another that is unused free space. Note: If an archive file is read-only, you cannot move the file in Windows File Explorer. To be able to move a read-only archive file, you must first remove the archive by selecting the file and selecting Remove in the Archive Maintenance page. |
| Generate Message on Data Update | Indicates whether an audit log entry will be made any time the value of a previously archived data point is overwritten. This log entry will contain both the original and new values. Note: To create multiple archives at the same time, select the Disabled option. This option is not available for SCADA Buffer data store. |