Embedded Database Options in WinCC OA V3.17
With the release of WinCC Open Architecture version 3.17 came the option of two embedded databases.
- History DB / Raima (HDB) – Existing options and available in V3.17 and previous versions
- Next Generation Archiver (NGA) – This is a new option that is based on InfluxDB and available in V3.17 and later versions
Referred to as RAIMA/HDB is an embedded database that allows the storage of different process data in each system layer. The functionality of parallel archiving to HDB and RDB is supported by WinCC OA. The RAIMA/HDB embedded database segments data in three primary areas:
- HDB – History Database used to save value changes
- RAIMA – Alarm Database used to save alarms
- Relational Database (RDB) – The current implementation of the RDB Archive Manager has been specially designed for Oracle databases.
About Next Generation Archiver
Starting with WinCC OA 3.17 the NextGen Archive (NGA) for WinCC OA is a new archiving solution which extends the flexibility while keeping the possibilities and strengths of the current methods.
The main features of the new NGA database are:
- Value changes and alarms using configuration concepts similar to already existing WinCC OA archiving solutions
- Compatible historical read interface (dpGetPeriod, dpGetAsynch, dpQuery with TIMERANGE, alert-GetPeriod)
- The direct read option to access underlying DB directly from CTRL code (User Interface, CTRL Manager)
- Modular DB backend that supports user-created DB backend interfaces
- Storage of values and alarms in multiple DBs / backends possible (“parallel archiving”) Modern time series DB InfluxDB® as default backend included in WinCC OA Reduced storage requirements) with RDB manager-compatible DB schema
- Usage of one DB for multiple WinCC OA systems
- DB maintenance (backup, restore, etc.)
- Redundant operation
Performance Data HDB vs. NGA
|Performance Metrics||History Database (HDB)||Next Generation Archiver (NGA)|
|Value changes per second||22,000 value changes per second||Up to greater than 30,000 value changes per second|
|Average data record size||48 bytes||less than 8 bytes|
Supported Read Rates
NGA operations are up to 3x as faster than HDB depending on the result size.