PVSS00ui - PARAM/SEVERE - HistQuery, constructAnswerMsg, archive request returns an error - too many values!

Enclosed you'll find the explanation for a log-message which can occur when a limit for historical queries was reached. The log-message is written to the PVSS_II.log-file.

PVSS00ui (1), 2011.10.06 09:08:03.554, PARAM,SEVERE, 54, Unexpected state, HistQuery, constructAnswerMsg, archive request returns an error - too many values!

Log-message with symbolic names:

PVSS00ui (1), <TIMESTAMP>, PARAM,SEVERE, 54, Unexpected state, HistQuery, constructAnswerMsg, archive request returns an error - too many values!

This log-message describes that a limit was reached when trying to read historical values from the database.
The limitation is made with the config-entries maxLinesInQuery and/or maxValueRequestCount in the [data]-section.

If the function getLastError() is used in the script where the function to read the historical data was started you’ll get the following error. When using the function throwError() the error is written to the PVSS_II.log-file.

If this error is reported please try to find out which historical 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. 1000000) 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”.