What does that have to do with the price of corn?

What does that have to do with the price of corn?

A rhetorical question calling attention to a non-sequitur or irrelevant statement or suggestion made by another person. Yes, I agree that health care is an important issue, but what does that have to do with the price of corn? We are discussing tax incentives for local businesses—not exactly a related topic!
See also: does, have, of, price, that, what
Farlex Dictionary of Idioms.
See also:
  • what does that have to do with the price of tea in China
  • What's that got to do with the price of meat?
  • What's that got to do with the price of tea in China?
  • What's that got to do with the price of cheese?
  • What's that got to do with the price of eggs?
  • What's that got to do with the price of fish?
  • apropos of nothing
  • Do bears crap in the woods?
  • Does a bear crap in the woods?