Importing CSV data to Exsiting MySQL Table?

I have a spreadsheet of details for 100 students.

It has columns for:

student_id, telephone_number, email_address, website

I also have a MySQL table of student details, with blank fields for telephone number, email, and web address. It already contains data in various other fields that I don’t want to touch. The student_id’s in the spreadsheet match those of the MySQL table.

What is the best/quickest way to import the spreadsheet data, matching up the student_ids ?