DataHub Historian

DataHub^® Historian is a high speed, low cost historical data storage mechanism that stores very little data per value change, so it has a very small on-disk footprint. The Historian comes with a disk space management feature that allows you to specify how much data to store for each point or how long to store the data and when to change the storage file names, all of which help to optimize storage on disk.

Technical summary

• Records point name, value, quality and timestamp and makes them available for rapid access.
• Utilizes in-memory caching, to store data in memory and periodically write data to disk. This allows for very high speed queries as some queries can be fully services by the memory cache, without having to read from the disk.
• But even when reading from disk, the Historian feature is capable of reading more than 1 million values per second on standard computer hardware.
• Highly efficient storage algorithms ensure no data gets dropped.
• History files are created, stored, and accessed automatically.
• In addition to straight queries of the raw data, the Historian also includes built-in query functions capable of producing analytical information which allows you to select any time period, from a few seconds to weeks, months, or longer, and retrieve averages, percentages of good and bad quality, time correlations, regressions, standard deviations, and more.
• Access to the Historian is available through the DataHub QuickTrend and WebView applications as well as through the built-in Gamma scripting language.
• Multiple deadbanding options lets you save space by eliminating repetitive or unnecessary values.

Vendor: Cogent Real-Time Systems

view complete profile

Founded in 1995, Cogent Real-Time Systems is the leader in real-time cross-platform data integration between Windows, Linux and QNX. Cogent serves industrial markets worldwide, primarily in North America, Europe, and Asia. Our clients are end-users and systems integrators who value high reliability and ease of use when connecting data-centric software in mission-critical systems.