0 votes 0 votes Is repetition allow in foreign key ? Give some reference Databases databases + – Prince Sindhiya asked Jan 18, 2019 Prince Sindhiya 358 views answer comment Share Follow See all 2 Comments See all 2 2 Comments reply arvin commented Jan 18, 2019 reply Follow Share https://stackoverflow.com/questions/7573590/can-a-foreign-key-be-null-and-or-duplicate 0 votes 0 votes prashant jha 1 commented Jan 18, 2019 reply Follow Share If no repetition was there , how can you maintain cardinalities other than one-one? 0 votes 0 votes Please log in or register to add a comment.