Introduction
INTERSECT
Instruction
Good. By default, UNION removes duplicate rows. Luckily, we can change this. Just put UNION ALL instead of UNION in your query
SELECT * FROM cycling WHERE country = 'Germany' UNION ALL SELECT * FROM skating WHERE country = 'Germany';
... and you'll get all rows, even when they are the same.
Exercise
Show all countries which have medals in cycling or skating. Use a union. Don't remove duplicates.
Stuck? Here's a hint!
Type:
SELECT country FROM cycling UNION ALL SELECT country FROM skating;
