Star Schema with R

I am a Business Intelligence Consultant working on OLAP cube and slowly learning R.Apologize if my question is a bit dummy orf/and been already answer but i am too new to know the correct keyword in order find an answer to my question. I read a book about R showing how to do deep analysis with R with is awesome but my day to day work is a way more simpler. All the database schema i am creating are Star Schema,so i am looking for the best way to deal with that with R. For exemple i have 4 tables one client(id_client,name), Region ( id_region,name) Time (id_time,day,month,semester,quarter,year) and a fact table (id,id_client,id_region,id_time,sale_amount,nbre_element,margin). So i am looking to do some SUM for all client for one region over time.Or doing Moving average ( in order to see trend). What the best way to deal with this kind of thing with R ( 99 % of my data-source are database and i only have one data-source for a project)
Hi,Thanks you very much,after retrieving the data into R.How to model a star schema into R ? What kind of data structure should i use ? What's the best way to slide and dice ? I wondering if there is tutorial for using R like an OLAP cube.

All the best