know as much about as a hog knows about Sunday

know as much about (something) as a hog knows about Sunday

To know absolutely nothing about something. Primarily heard in US. My uncle bequeathed the farm to me when he passed away, but I knew as much about running a farm as a hog knows about Sunday! Oh, stop lecturing me. You know as much about running a business as a hog knows about Sunday!
See also: hog, know, much, Sunday
Farlex Dictionary of Idioms.

know as much about something as a hog knows about Sunday

Rur. to have no knowledge of something. Don't let Jim make dessert for the picnic. He knows as much about pies as a hog knows about Sunday. I had quite a time changing the tire, since I know as much about cars as a hog knows about Sunday.
See also: hog, know, much, Sunday
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • know as much about (something) as a hog knows about Sunday
  • know as much about (something) as a pig knows about Sunday
  • bedsheets
  • be on the danger list
  • be on/off the danger list
  • be off the danger list
  • elope
  • elope to Gretna Green
  • bequeath (something) to (someone)
  • bequeath to