I have a Report Viewer that takes optional parameters based on user input. If a value is not entered, I want to pass a null value to that parameter in the Report Viewer’s props.params. However, when I do this, I get a warning: ‘Error executing query parameter expression “{paramName}”’
If I leave out the parameter, It will take the default value in the report. If I put a null or None value as the default, I get the same error in the Report Designer.
I’ve tried null, Null, and None.
Try an expression binding with the expression null.
If you just write null into the JSON editor, you're creating a string value "null", not an actual absence-of-value.
My parameters are added by python scripting. This option would require me to rewrite the script but I’ll look into this. Thank you.
Then just have the script omit nulls from the parameter dictionary.
I don't think you will ever fix this. Null is the actual signal to use the report default.
Make the report default to null instead.
I get this whenever I put Null, None or any other variation of null in the Default Value.
Perhaps it is time to make a formal feature request.