ASP.NET MVC Drop DownList

Question

Question:

 

 

In My table (ALBUM) I have 3 colums like Id,album title, category name and i am bind the category name column into dropdownlist. But Category Name consist Duplicate Values. How to access the unique value from the database and bind to dropdownlist in ASP.NET MVC.? In this process database doesn't effected. How to access the data without effecting changes in the database?