My toilet drain pipe has a small leak where two pipes connect. Is there a way I can repair the connection leak without taking the connection apart?

More details please!
What material are the pipes? At what fitting is the leak? How are the two pipes connected? A picture would be nice. Back to you, Tom

Have problem with pipes coming from my toilet into sewrage , after having a blockage a company came out and cleaned the drain with pressure washer then he too a photo of inside the pipes to see why it keeps blocking and they found that 2 pipes that join one has slipped and covering part of the other one so instead of having a 4 inch for toilet water its now only 2 inches so the dropped pipe needs lifting.. how difficult will this be its about 18 inches under soil