Best way to Show Complex and Lengthy Table Headings

Question

So I have been creating a design for a table in which there is

Heading Tr1=> Roll | Name | Subjects      | Subjects | Subjects |||| | Aggregate |

Heading Tr2=>             |part|part|total|

Now the problem is that I don't control the part names, it's a user input. If I use the part name directly in the 2nd row then it can result in very wide columns while the data for there columns are usually 2 digit numerical numbers.

Approach I am using is that I am replacing part names by P1,P2,P3 along with info icon which on clicking show a popover containing the name and marks related to a part. As Follow:

Answer 1

Keep aggregate only. Let Users drill down the information on demand for each row by either:

• presenting details in one extra row appearing under row of choice

• presenting details in separate table

• presenting details in tooltip in vertical way for many parts