How to read structured Excel Data into database ?

Question

Hi,

I am developing a webApp that will take data from an Excel workbook and store the info in the database.

MY problem is that, the Excel data is structured in the following way :

Category | Course | Topics

Now for one category, there can be many courses and each course can have many topics.

So its a 1:Many relationship between each of those columns.

Now here is an Example :


Category   |   Course      |   Topics

Cat 1             Course1          Topic1
                                             Topic2
                                             Topic3
                                             Topic4
                                             Topic4

Cat 2            Course2            Topic1
                                               Topic2

.
.
.
.
.
.
.
.

ETC/.....

So how can I write a code or use some method of the DataTable which will read all the Courses that belong to one particular category ? Or all the topics in one particular course ?