Macro To Concatenate Based On Entered Date

I have attached a spreadsheet illustrating my query.

I would like to run a sub procedure called generatedataset then I'd like to enter a date from column J (starting from J4) into G12 ( cell G12 is a named range called effective_date). Then enter the concatenation of the adjacent cells K4 and L4 and place this into cell G9 (cell G9 is a named range called dataset_name). Then call the procedure again. Repeating for all values in range starting at J4 extending down, and for all corresponding concatenated values in K and L.

Data would always be taken from columns J or K&L and placed in the same cells ie G12 (named range effective_date) and G9 (named range dataset_name) respectively.