WCCOAui/WCCOActrl - IMPL/SEVERE - DataManRequestHandler, constructAnswerMsg, request returns an error (too many values?)

Enclosed you'll find the explanation for a log-message which can occur during runtime when trying to read historical alert information from the database. The log-message is written to the PVSS_II.log-file.

WCCOAui (1), 2014.06.02 15:11:08.257, IMPL, SEVERE, 54, Unexpected state, DataManRequestHandler, constructAnswerMsg, request returns an error (too many values?)

Log-message with symbolic names:

WCCOAui (1), <TIMESTAMP>, IMPL, SEVERE, 54, Unexpected state, DataManRequestHandler, constructAnswerMsg, request returns an error (too many values?)

This log-messages describes that a limit for historical alert requests was reached.
The limitation is made with the config-entry maxAlertRequestCount in the [data]-section.

If the function getLastError() and throwError() is used in the script which is starting the alertGetPeriod()-function to read historical information the error is written to the PVSS_II.log-file.

If this error is reported please try to find out which historical alert query was started and afterwards check if this query should be allowed or not. The maximum value has to be defined in discussion with the users operating the plant.

Please do not increase the value for the config-entry to a very high value (e.g. 2000000) or set it to 0 (no limitation).

The limitation for queries is part of the system stability functions in WinCC OA. For details please have a look at the online-help, search for the keywords “Error tolerance” and “stability”.