PVSS00ui - PARAM/SEVERE - Query not successful: Too many values

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

PVSS00ui (1), 2011.10.06 17:21:22.527, PARAM,SEVERE, 54, Unexpected state, Query not successful: Too many values

Log-message with symbolic names:

PVSS00ui (1), <TIMESTAMP>, PARAM,SEVERE, 54, Unexpected state, Query not successful: Too many values

This log-message describes that the query would return too many values.
If the function getLastError() is used in the script where the function to read the 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 only this error is reported a possible cause could be that the limit for maxDpNamesCount in the event-manager is reached. This can happen especially in projects with a lot of dp-elements if a query was made for all dp-elements or nearly all of them (FROM-filter at the query-statement).

If this error is reported please 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 (at the [event]-section to a very high value (e.g. 10000000) 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”.