Factual error: Dean Martin always drank apple juice when he was on stage because it looked so much like scotch and water and he had to keep up his reputation of being a heavy drinker who forgets where he is.

Continuity: When they are on stage you see Sammy standing next to Joey having a conversation. The camera angle changes and Joey is now standing by himself and Sammy is on the other side of the stage with Peter.

Continuity: Joey is standing at the mic giving insults to Frank and Dean and he's standing there with his arms folded across his chest. The camera angle changes and his hands are now in his pockets.

Continuity: When Sammy is singing, Frank comes over and leans into the mic to sign with him. The camera angle changes and his arm is now around Sammy's shoulder.

Continuity: When Sammy and May are arguing at the party, Sammy is seen looking down at the ground when the camera angle is from the front, and when the camera angle is from the back he's seen looking straight at her. Happens twice during the scene.