Historical Data, Alarm, and Event Files in Citadel 4
PrintOverview
Citadel 4 database is used for historical data storage by Lookout and the LabVIEW Datalogging and Supervisory Control Module.
Historical Data Files
Historical data is contained in the following collection of files. | File Name | Description |
| thd00001.thd | Stores the actual historical data. Contains the pages of data from the traces. Each page is 4096 bytes. There are 256 pages per file, with 256 additional bytes of header information. |
| tdb.tdb | This file defines the database. It includes trace names, database version info, similar information. If this file is lost or corrupted, you will need the backup file to recover. |
| tdb.bak | The backup for the tdb.tdb file. If both this file and the tbd.tbd file are lost or corrupted, data cannot be recovered. |
| tdx.tdx | Temporary meta block and page index. This contains a quick-lookup index for the components of a trace. This file will be regenerated if lost. The disadvantage is that it takes a while to regenerate if your database is large. |
Alarm and Event Files
Alarm and event data are contained in files with the Ale prefix. Files with the .adx extension can be regenerated if they are lost or damaged.
| File Name | Description |
| Ale00000.ale | Stores the actual body of alarm and event data. |
| Aleack00000.adx | Quick lookup index for currently acknowledged alarms that have not been reset. |
| Aleset00000.adx | Quick lookup index for currently set alarms that have not been acknowledged. |
| AleIdx00000.adx | Lookup Index of all alarms in the ALE files. |
| areas.dat | Stores alarm areas. |
| mdx.mdx | Top-level meta-index. This is similar to tdx.tdx in that it can be regenerated if lost. This file increases the speed of opening the database. |
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