Dynamically how to design pie chart Report based on DB data in SSRS

Hi All,

i need to dynamically generate pie chart report in SSRS 2008 R2. For example i have HR and IT dept. In my DB i have data for the same. IF i generate report both will come dynamically and one more total pie chart has to be display at the top. suppose i Added two more dept table in my Db like Admin and security. now me going to preview  report so four pie chart has to come along with total pie chart too at the top of the report. no need to pass any parameter just preview report based on data. if i added more dept than pie chart has to be come dynamically.

how can we achieve this requirement , plz  suggest me with example(if possible rdl and Sp also needed for demo).

thanks in advance.

regards,

Akhil