Hi Mohameddba,
It is better that the database developer knows one or some .Net language because our database usually communicates with these kind of applications, and some technology requires .Net Framework background, such as: CLR Integration, but there are also some
database developers have no programming background, they just focus on other database develop fields, such as: to create table, index, stored procedure, etc. You can refer to the following document to learn how to design database.
Designing Databases
http://msdn.microsoft.com/en-us/library/ms187099(v=sql.105).aspx
Allen Li
TechNet Community Support
