What are the responsibilities of database administrators and database designers?

It depends on the nature of the job. Supposing you are the database manager in cancer research, then you will have to organise the patient's data with respect to a particular treatment, say for example radiation treatment. It will be more like a retrospective study. Or your job might be to enter the data in tables, organise using Microsoft access or Excel and you may also have to perform simple data analysis. Your job might also include writing reports and contributing to publications etc. I guess the responsibilties are diverse and entail many areas. Hope this helps Thank you Good luck