Creating a datatable using data from database

Hi, how can I create a datatable from a table in my database.

I want to be able to use the datatable to perform calculations such as averaging a number of grades of different students.

Im currently using this which is inside a dataset sub, is there any way to just use the "completed_module" table without the use of a dataset?

Dim avgTable As DataTable
avgTable = dataSet.Tables("completed_module")