I am looking to build out my SQL database but don't yet have all the data. I know what dimension and measures I want to create but don't have all the data for it. For example I am looking to build out our Revenue forecast model for the next 5 year and would like to set up a data cube to capture all of the pieces to this revenue model as the data becomes available. Some of these pieces will be forecast data for 2016-2020. Several questions....is there a way in SQL to add in the basic structure of the cube (like year, 2016, 2017, 2018, etc...) and add the data later?

Also what OLAP tool could I use to manage the data and populate it at a later date? Ideally I would like to have something like an Excel pivot table that people could set up themselves where then can get the data view they are looking for and then add in data via the pivot table design and have it write back to the database. Same way Oracle's Smartview addin for excel allows users to query the data view they want and be able to write back to the HFM database. Is there a way either through Excel pivot table or some excel addin that will allow me to write and save data to the database? And is there a tool that will allow me to add additional dimension values, like years to the year field as I move forward? For example let's say I want to add in years 2021-2025 now, is there a tool that will allow me to append these years to the "year" field dimension?

Thanks!