Ran into this question on the BOBJ board asking how to create a WEBI report which can prompt the user to enter the start and end dates for running a report. Seems quite simple and useful so here is the solution.
I am using the adventure works universe to illustrate the process. The query I have created is show below.
Created a simple query which prompts the user to enter the year and months for analysis. Note that I will only allow the user to select a single year. If you want to do cross-year analysis then you would need to define a separate object in the time dimension as which would allow the user to perform cross year analysis. When I run the report I get prompted to enter the year and months for the report.
And the results are as shown.
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