SELECT name, cost, bids FROM items WHERE bids >100
UNION
SELECT name, cost, bids FROM items WHERE cost >200
UNION ➔ This simple keyword joins a two queries' results into one data set. If you did the above without union, the query would effectively be run twice and give you two datasets. Useful for complex filtering. NOTE: When using unions, your columns must be the same for both queries.
SELECT name, cost, bids FROM items WHERE bids >100
UNION ALL
SELECT name, cost, bids FROM items WHERE cost >200
UNION ALL ➔ Allows you to