I have implemented a Database Logger for WinCC OA which supports different databases.
I did now a first test to compare some databases with WinCC OA and time series logging.
The logger is writing 1000 values/second to four databases in parallel: MSSQL Server, InfluxDB, Phoenix (based on Hadoop/HBase) and Oracle.
There are now about 160.000.000 values in each database.
Four Ctrl-Scripts are querying data with dpGetPeriod every 10 seconds, random time frames (between 1 and 2 hours of data).
See the result: