I'm working through one of the standard C# SDK samples and I have a question. The PIData.RecordedValues method takes a filter expression. When I run the sample I get an exception:
Failed to retrieve events from server. [-12301] Performance Equation parsing error
This is the code in the sample (slightly modified to use PITimeFormat params, instead of strings):
pvsArchivedValues = _ptPIPoint.Data.RecordedValues(start.LocalDate, end.LocalDate, BoundaryTypeConstants.btOutside, "*", FilteredViewConstants.fvRemoveFiltered, null);
It seems like the filter expression is bad (hense the parse error) since when I make it an empty string, the call works. What kinds of expressions are used to filter the results, and why would there have been a "*" in there in the first place?