Question

I have written and passed 70-433 (SQL 2008 MCTS exam) and was reviewing when I realised that I have been doing what INTERSECT does with a WHERE IN subquery, as well as EXCEPT with a WHERE NOT IN subquery.

Are there any differences between using the new commands instead of subqueries?

Answer 1

INTERSECT and EXCEPT compare all the selected values in the rows returned while WHERE IN and WHERE NOT IN only compare one column at a time.

SELECT name,date from customers
EXCEPT
SELECT name, date from orders