I got this to work by combining a few suggestions. I did not like the idea of hacking the Reporting Services tables, or subverting the normal scheduling. The suggestion to throw an error seemed the best, but did not make sense. Finally, I was able to create a stored procedure with a parameter that said whether to allow for an empty result set or not. Example:

CREATE PROCEDURE usp_getReportData @StartDate DATETIME = null, @EndDate DATETIME = null, @AllowEmptyReturn BIT = 1

AS

BEGIN

IF NOT Exists(SELECT TOP 1Data1, Data2 FROM DataTable

WHERE Data2 BETWEEN @StartDate AND @EndDate)

AND @AllowEmptyReturn = 0

BEGIN

RAISERROR ('No Records Found',16,1)

END

ELSE

BEGIN

SELECT Data1, Data2 FROM DataTable

WHERE Data2 BETWEEN @StartDate AND @EndDate

END

END