Can CR formulas be used in the SQL for database queries or are we limited to parameters alone?

I need to create a parameter that a user can select to indicate they want to see current or previous quarter data.

For lack of a better way I have created a parameter with values of 0 for current and -1 for previous quarter. The parameter is passed to one of two formulas that call a function providing either the start date or end date of the requested quarter. I have placed the formula name in braces in the SQL but I am guessing the formula isn't evaluated early enough to work in the SQL query.

If this is the case how then can you create a parameter that will provide the start and end dates for the requested quarter? Are we left with just expecting the user to manually enter or select the dates?

Thank you for your response. The problem is that I need to pass the parameter to the Oracle database to perform record filtering. If I didn't it would take forever for the report to perform filtering. The parameter value prompt for the command is real weak but I guess we'll just have to live with it.

Thanks again and apologies for not getting back to this sooner.