In the database

[Xinfu]

Are in and on the same and equally correct?

-You don't have to take pictures of the exam papers. The exam questions will be available in/on the database online.

-Sorry, I can't go and dine with you tonight. I still have to make final touch on/in the essay before handing it in tomorrow to the teacher.

[Rusty]

They are the same and equally correct.

... have to make a final touch ...
-or-
... have to make final touches ...

[Xinfu]

Thank you.