Does adding olive oil in pasta while boiling make it sticky?
Some people think adding olive oil to pasta water will keep the pasta from sticking, but in reality it does absolutely nothing. Adding a tablespoon of oil to pasta water won't affect the outcome in the slightest, doing that is a waste of a good ingredient. 

Adding olive oil to pasta after it has been drained on the other hand will keep the pasta from sticking. It will also make it oily, which may not be what you want.